Locomotion and Movement - Comprehensive Question Paper

Section A: Multiple Choice Questions (MCQs) - 100 Questions

1. Which of the following is an example of amoeboid movement? a) Movement of Paramecium b) Movement of spermatozoa c) Movement of leucocytes d) Movement of Euglena

2. The functional unit of muscle contraction is: a) Myofibril b) Sarcomere c) Actin filament d) Myosin filament

3. How many bones are present in the human skull? a) 22 b) 26 c) 28 d) 24

4. The lighter band in a sarcomere is called: a) A-band b) I-band c) H-zone d) M-line

5. Which type of joint allows maximum movement? a) Fibrous joints b) Cartilaginous joints c) Synovial joints d) Fixed joints

6. The vertebral column consists of how many vertebrae? a) 24 b) 26 c) 28 d) 30

7. Myasthenia gravis affects: a) Bone formation b) Joint movement c) Neuromuscular junction d) Cartilage formation

8. The pectoral girdle consists of: a) Clavicle and scapula b) Ilium and ischium c) Humerus and radius d) Femur and tibia

9. Which neurotransmitter is released at the neuromuscular junction? a) Dopamine b) Serotonin c) Acetylcholine d) GABA

10. Ciliary movement is seen in: a) Amoeba b) Paramecium c) Euglena d) Plasmodium

11. The central part of A-band containing only myosin is: a) I-band b) Z-line c) H-zone d) M-line

12. How many pairs of ribs are there in humans? a) 10 b) 11 c) 12 d) 13

13. Osteoporosis is commonly caused by decreased levels of: a) Testosterone b) Insulin c) Estrogen d) Growth hormone

14. The knee joint is an example of: a) Ball and socket joint b) Hinge joint c) Pivot joint d) Gliding joint

15. Cardiac muscles are: a) Striated and voluntary b) Non-striated and voluntary c) Striated and involuntary d) Non-striated and involuntary

16. The ear ossicles include: a) Malleus, incus, stapes b) Hyoid, maxilla, mandible c) Radius, ulna, humerus d) Femur, tibia, fibula

17. Gout is caused by accumulation of: a) Calcium crystals b) Uric acid crystals c) Cholesterol crystals d) Protein crystals

18. The axial skeleton does NOT include: a) Skull b) Vertebral column c) Pectoral girdle d) Sternum

19. Smooth muscles are found in: a) Heart b) Skeletal system c) Internal organs d) Voluntary muscles

20. The region between two successive Z-lines is: a) A-band b) I-band c) Sarcomere d) H-zone

21. Floating ribs are: a) 1st-7th pairs b) 8th-10th pairs c) 11th-12th pairs d) All ribs

22. Tetany is caused by low levels of: a) Sodium b) Potassium c) Calcium d) Magnesium

23. The thumb joint is an example of: a) Hinge joint b) Ball and socket joint c) Saddle joint d) Pivot joint

24. Sarcoplasmic reticulum stores: a) ATP b) Calcium ions c) Sodium ions d) Potassium ions

25. The longest bone in the human body is: a) Humerus b) Tibia c) Femur d) Fibula

26. Flagellar movement is seen in: a) Amoeba b) Paramecium c) Euglena d) Plasmodium

27. The dark band in sarcomere is: a) A-band b) I-band c) H-zone d) Z-line

28. How many cervical vertebrae are there? a) 5 b) 7 c) 12 d) 26

29. Arthritis is: a) Inflammation of bones b) Inflammation of joints c) Inflammation of muscles d) Inflammation of cartilage

30. The shoulder joint is: a) Hinge joint b) Ball and socket joint c) Pivot joint d) Gliding joint

31. Muscle fibres are: a) Uninucleated b) Binucleated c) Multinucleated d) Without nucleus

32. The appendicular skeleton includes: a) Skull and vertebrae b) Ribs and sternum c) Limbs and girdles d) All of the above

33. Cross-bridges are formed between: a) Actin and troponin b) Myosin and tropomyosin c) Actin and myosin d) Troponin and tropomyosin

34. How many thoracic vertebrae are present? a) 5 b) 7 c) 12 d) 26

35. The atlas and axis joint is: a) Hinge joint b) Ball and socket joint c) Pivot joint d) Gliding joint

36. Syncytium refers to: a) Single nucleated cell b) Multinucleated cell c) Cell without nucleus d) Cell with two nuclei

37. How many metacarpals are there in one hand? a) 3 b) 5 c) 7 d) 8

38. The M-line bisects: a) A-band b) I-band c) H-zone d) Sarcomere

39. Sutures are examples of: a) Synovial joints b) Cartilaginous joints c) Fibrous joints d) Movable joints

40. During muscle contraction, which zone decreases? a) A-band b) I-band c) Both A and I bands d) Neither A nor I bands

41. The hyoid bone is part of: a) Appendicular skeleton b) Axial skeleton c) Both d) Neither

42. Phalanges are: a) Bones of fingers and toes b) Bones of wrist c) Bones of ankle d) Bones of palm

43. Energy for muscle contraction comes from: a) ADP b) ATP c) AMP d) Glucose

44. The pelvic girdle consists of: a) One coxal bone b) Two coxal bones c) Three coxal bones d) Four coxal bones

45. Troponin is associated with: a) Thick filament b) Thin filament c) Z-line d) M-line

46. How many lumbar vertebrae are there? a) 5 b) 7 c) 12 d) 26

47. The patella is: a) Thigh bone b) Shin bone c) Kneecap d) Ankle bone

48. Calcium is pumped back into sarcoplasmic reticulum during: a) Muscle contraction b) Muscle relaxation c) Both contraction and relaxation d) Neither contraction nor relaxation

49. True ribs are: a) 1st-7th pairs b) 8th-10th pairs c) 11th-12th pairs d) All ribs

50. The sternum is located: a) On the back b) On the ventral midline c) On the side d) Inside the abdomen

51. Myofibrils are composed of: a) Sarcomeres b) Nuclei c) Mitochondria d) Ribosomes

52. How many tarsals are there in one foot? a) 5 b) 7 c) 8 d) 14

53. The action potential spreads through: a) Sarcolemma b) Sarcoplasm c) Sarcoplasmic reticulum d) All of the above

54. False ribs are: a) 1st-7th pairs b) 8th-10th pairs c) 11th-12th pairs d) All ribs except true ribs

55. The hip joint is: a) Hinge joint b) Ball and socket joint c) Pivot joint d) Gliding joint

56. Myosin heads are also called: a) Thin filaments b) Cross-bridges c) Z-lines d) A-bands

57. How many carpals are there in one hand? a) 5 b) 7 c) 8 d) 14

58. The power stroke involves: a) ATP synthesis b) Calcium release c) Myosin pulling actin d) Muscle relaxation

59. Coccygeal vertebrae are: a) 1 fused b) 5 separate c) 7 separate d) 12 separate

60. The elbow joint is: a) Ball and socket joint b) Hinge joint c) Pivot joint d) Saddle joint

61. Fascicles are: a) Individual muscle fibres b) Muscle bundles c) Protein filaments d) Bone fragments

62. The fibula is located in: a) Upper arm b) Forearm c) Thigh d) Lower leg

63. During muscle contraction, myosin binding sites are exposed on: a) Tropomyosin b) Troponin c) Actin d) Z-line

64. Sacral vertebrae are: a) 1 fused b) 5 fused c) 7 separate d) 12 separate

65. Carpal joints are examples of: a) Hinge joints b) Ball and socket joints c) Gliding joints d) Pivot joints

66. The cytoplasm of muscle fibre is called: a) Cytosol b) Sarcoplasm c) Nucleoplasm d) Protoplasm

67. The radius is located in: a) Upper arm b) Forearm c) Thigh d) Lower leg

68. ATP is required for: a) Cross-bridge formation b) Cross-bridge detachment c) Both formation and detachment d) Neither formation nor detachment

69. How many bones are in the facial region? a) 8 b) 14 c) 22 d) 26

70. The tibia is: a) Thigh bone b) Shin bone c) Calf bone d) Ankle bone

71. Tropomyosin blocks myosin binding sites on: a) Thick filament b) Thin filament c) Z-line d) M-line

72. The cranium consists of: a) 8 bones b) 14 bones c) 22 bones d) 26 bones

73. The ulna is part of: a) Upper arm b) Forearm c) Thigh d) Lower leg

74. Muscle relaxation occurs when: a) Calcium is released b) Calcium is removed c) ATP is hydrolyzed d) Myosin binds to actin

75. Metatarsals are found in: a) Hand b) Foot c) Wrist d) Ankle

76. The endoplasmic reticulum of muscle is called: a) Smooth ER b) Rough ER c) Sarcoplasmic reticulum d) Golgi apparatus

77. The humerus is located in: a) Forearm b) Upper arm c) Thigh d) Lower leg

78. Cross-bridge detachment requires: a) Calcium b) ATP c) ADP d) Phosphate

79. How many phalanges are in one hand? a) 5 b) 8 c) 14 d) 19

80. The neuromuscular junction is between: a) Two neurons b) Neuron and muscle c) Two muscles d) Muscle and bone

81. Pseudopodia are formed by: a) Cilia b) Flagella c) Streaming protoplasm d) Muscle contraction

82. The scapula is part of: a) Axial skeleton b) Appendicular skeleton c) Both d) Neither

83. The I-band contains: a) Only actin b) Only myosin c) Both actin and myosin d) Neither actin nor myosin

84. How many bones are in one upper limb? a) 28 b) 30 c) 32 d) 34

85. Muscle contraction is initiated by: a) ATP b) Calcium c) Neural signal d) All of the above

86. The clavicle connects: a) Arm to shoulder b) Shoulder to trunk c) Leg to hip d) Hip to trunk

87. The A-band contains: a) Only actin b) Only myosin c) Mostly myosin d) Neither actin nor myosin

88. How many bones are in one lower limb? a) 28 b) 30 c) 32 d) 34

89. Rigor mortis is due to: a) Excess ATP b) Lack of ATP c) Excess calcium d) Lack of calcium

90. The sternum consists of how many parts? a) 1 b) 2 c) 3 d) 4

91. Skeletal muscles are: a) Voluntary and striated b) Involuntary and striated c) Voluntary and non-striated d) Involuntary and non-striated

92. The acetabulum is part of: a) Shoulder joint b) Hip joint c) Knee joint d) Elbow joint

93. The sliding filament theory explains: a) Bone movement b) Joint movement c) Muscle contraction d) Blood circulation

94. The glenoid cavity is part of: a) Hip joint b) Shoulder joint c) Knee joint d) Elbow joint

95. Calcium binds to: a) Actin b) Myosin c) Troponin d) Tropomyosin

96. The vertebral column protects: a) Heart b) Lungs c) Spinal cord d) Brain

97. ATPase activity is present in: a) Actin b) Myosin c) Troponin d) Tropomyosin

98. The rib cage protects: a) Heart and lungs b) Liver and kidneys c) Brain and spinal cord d) Stomach and intestines

99. The power stroke results in: a) Muscle elongation b) Muscle shortening c) Muscle relaxation d) No change in muscle length

100. The skull protects: a) Heart b) Lungs c) Brain d) Spinal cord

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Section B: One Mark Short Questions - 100 Questions

1. Define locomotion.
2. What is amoeboid movement?
3. Name the protein filaments in sarcomere.
4. How many bones are in the human skull?
5. What is the functional unit of muscle?
6. Define movement.
7. Give an example of ciliary movement.
8. What is the axial skeleton?
9. Name the neurotransmitter at neuromuscular junction.
10. What causes tetany?
11. Define sarcomere.
12. How many ribs are there in humans?
13. What is myasthenia gravis?
14. Name the components of pectoral girdle.
15. What is the I-band?
16. Define arthritis.
17. Give an example of flagellar movement.
18. What is osteoporosis?
19. Name the ear ossicles.
20. What is the H-zone?
21. Define gout.
22. How many vertebrae are in vertebral column?
23. What is sarcoplasm?
24. Name the types of ribs.
25. What is a syncytium?
26. Define appendicular skeleton.
27. What is the A-band?
28. How many cervical vertebrae are there?
29. What is cross-bridge?
30. Name the components of pelvic girdle.
31. What is Z-line?
32. How many thoracic vertebrae are present?
33. Define fascicle.
34. What is M-line?
35. How many lumbar vertebrae are there?
36. What is sarcolemma?
37. Name the longest bone in human body.
38. What is sarcoplasmic reticulum?
39. How many pairs of floating ribs are there?
40. Define myofibril.
41. What is patella?
42. How many metacarpals are in one hand?
43. What is troponin?
44. Name the bones of forearm.
45. What is tropomyosin?
46. How many phalanges are in one hand?
47. Define power stroke.
48. What is acetabulum?
49. How many carpals are in one hand?
50. What is glenoid cavity?
51. How many tarsals are in one foot?
52. Define rigor mortis.
53. What is clavicle?
54. How many metatarsals are in one foot?
55. What is scapula?
56. Name the thigh bone.
57. What is fibula?
58. Name the shin bone.
59. What is humerus?
60. Name the bones of upper arm.
61. What is radius?
62. Name the kneecap.
63. What is ulna?
64. How many bones are in cranium?
65. What is sternum?
66. How many facial bones are there?
67. Define hyoid bone.
68. What causes osteoporosis?
69. Name the calf bone.
70. What is the function of calcium in muscle contraction?
71. Define neuromuscular junction.
72. What is the role of ATP in muscle contraction?
73. Name the three types of muscles.
74. What is the difference between movement and locomotion?
75. Define joint.
76. What are sutures?
77. Name the movable joints.
78. What is ball and socket joint?
79. Give example of hinge joint.
80. What is pivot joint?
81. Define gliding joint.
82. What is saddle joint?
83. Name the immovable joints.
84. What are cartilaginous joints?
85. Define synovial joints.
86. What is synovial fluid?
87. Name the voluntary muscles.
88. What are involuntary muscles?
89. Define striated muscles.
90. What are non-striated muscles?
91. Where are cardiac muscles found?
92. What is the function of skeleton?
93. Define bone.
94. What is cartilage?
95. Name the hardest tissue in body.
96. What is bone marrow?
97. Define fracture.
98. What is dislocation?
99. Name the smallest bone in human body.
100. What is the function of ribs?

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Section C: Two Marks Questions - 100 Questions

1. Differentiate between movement and locomotion with examples.
2. Describe amoeboid movement with examples.
3. Explain ciliary movement and give two examples.
4. What is flagellar movement? Give examples.
5. List the components of axial skeleton.
6. Describe the structure of skull mentioning number of bones.
7. Explain the composition of vertebral column.
8. What are the different types of ribs? Mention their numbers.
9. List the components of appendicular skeleton.
10. Describe the pectoral girdle and its function.
11. Explain the structure of pelvic girdle.
12. List the bones of upper limb with their numbers.
13. Name the bones of lower limb with their numbers.
14. Differentiate between axial and appendicular skeleton.
15. What are joints? Classify them based on movement.
16. Describe fibrous joints with examples.
17. Explain cartilaginous joints with examples.
18. What are synovial joints? Give examples.
19. Differentiate between ball and socket joint and hinge joint.
20. Compare skeletal, smooth, and cardiac muscles.
21. Describe the structure of skeletal muscle fiber.
22. What is sarcomere? Explain its components.
23. Differentiate between actin and myosin filaments.
24. Explain the banding pattern of sarcomere.
25. What is the role of calcium in muscle contraction?
26. Describe the neuromuscular junction.
27. Explain the role of acetylcholine in muscle contraction.
28. What happens during the power stroke?
29. Describe muscle relaxation process.
30. What is cross-bridge cycle?
31. Explain the role of ATP in muscle contraction.
32. What are the symptoms of myasthenia gravis?
33. Describe tetany and its cause.
34. What is arthritis? Mention its types.
35. Explain osteoporosis and its causes.
36. What is gout? Describe its symptoms.
37. Compare true ribs, false ribs, and floating ribs.
38. Describe the structure and function of sternum.
39. What are the functions of skeletal system?
40. Explain the difference between bone and cartilage.
41. What is the significance of synovial fluid?
42. Describe the structure of synovial joint.
43. What are the types of movements possible at joints?
44. Explain flexion and extension movements.
45. What is abduction and adduction?
46. Describe rotation and circumduction movements.
47. What is the function of ligaments?
48. Explain the role of tendons.
49. What are the characteristics of skeletal muscles?
50. Describe the properties of smooth muscles.
51. What are the features of cardiac muscles?
52. Explain voluntary and involuntary muscles.
53. What is the difference between striated and non-striated muscles?
54. Describe the microscopic structure of skeletal muscle.
55. What is the role of sarcoplasmic reticulum?
56. Explain the function of T-tubules.
57. What is excitation-contraction coupling?
58. Describe the sliding filament mechanism.
59. What happens during muscle fatigue?
60. Explain oxygen debt in muscles.
61. What is the all-or-none law of muscle contraction?
62. Describe isotonic and isometric contractions.
63. What is muscle tone?
64. Explain motor unit.
65. What is the role of motor neuron in muscle contraction?
66. Describe the graded response in muscles.
67. What is summation in muscle contraction?
68. Explain tetanus in muscle physiology.
69. What are fast and slow twitch muscle fibers?
70. Describe the energy sources for muscle contraction.
71. What is creatine phosphate system?
72. Explain anaerobic glycolysis in muscles.
73. What is the role of myoglobin in muscles?
74. Describe muscle hypertrophy and atrophy.
75. What are the effects of exercise on muscles?
76. Explain the importance of warm-up before exercise.
77. What causes muscle cramps?
78. Describe the healing process of bone fractures.
79. What is the role of calcium and phosphorus in bones?
80. Explain the importance of vitamin D for bones.
81. What are the effects of aging on skeletal system?
82. Describe the gender differences in skeletal system.
83. What is the role of hormones in bone development?
84. Explain the process of ossification.
85. What are growth plates in bones?
86. Describe the blood supply to bones.
87. What is the lymphatic drainage of bones?
88. Explain the innervation of skeletal muscles.
89. What are the postural muscles?
90. Describe the muscles of facial expression.
91. What are the muscles of mastication?
92. Explain the respiratory muscles.
93. What are the core muscles?
94. Describe the limb muscles.
95. What is the role of proprioception in movement?
96. Explain balance and coordination.
97. What are reflexes in relation to movement?
98. Describe the role of cerebellum in movement.
99. What is the motor cortex?
100. Explain the spinal control of movement.

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Section D: Three Marks Broad Questions - 100 Questions

1. Describe the different types of movements in organisms with suitable examples and explain their significance.

2. Give a detailed account of the human skeletal system, including its divisions and major components.

3. Explain the structure of human skull in detail, mentioning the number and names of bones in cranium and face.

4. Describe the vertebral column of humans, including the number, types, and functions of different vertebrae.

5. Give a comprehensive account of the appendicular skeleton, including the girdles and limb bones.

6. Classify joints based on structure and function. Describe each type with suitable examples.

7. Explain the structure and function of synovial joints in detail with examples of different types.

8. Describe the microscopic structure of skeletal muscle fiber, including all its components and their functions.

9. Give a detailed explanation of the sarcomere structure and the arrangement of protein filaments.

10. Explain the sliding filament theory of muscle contraction step by step with molecular details.

11. Describe the role of calcium ions in muscle contraction and relaxation processes.

12. Explain the events at the neuromuscular junction during muscle stimulation.

13. Give a detailed account of the cross-bridge cycle in muscle contraction.

14. Describe the energy requirements and ATP utilization during muscle contraction and relaxation.

15. Explain the disorders of the muscular system: myasthenia gravis, tetany, and their causes.

16. Describe the disorders of the skeletal system: arthritis, osteoporosis, and gout with their causes and symptoms.

17. Compare and contrast the three types of muscles in terms of structure, location, and function.

18. Explain the process of excitation-contraction coupling in skeletal muscles.

19. Describe the different types of muscle contractions: isotonic, isometric, and their physiological significance.

20. Explain muscle fatigue, its causes, and the recovery process including oxygen debt.

21. Describe the structure and function of the pectoral girdle and its articulations.

22. Give a detailed account of the pelvic girdle, its components, and gender differences.

23. Explain the structure and functions of the rib cage, including the classification of ribs.

24. Describe the bones of the upper limb in detail, including their articulations and functions.

25. Give a comprehensive account of the bones of the lower limb and their functional significance.

26. Explain the development and growth of bones, including the role of growth plates and hormones.

27. Describe the composition and properties of bone tissue, including compact and spongy bone.

28. Explain the process of bone remodeling and repair, including the role of osteoblasts and osteoclasts.

29. Describe the blood supply and innervation of bones and muscles.

30. Explain the role of various nutrients and vitamins in maintaining healthy bones and muscles.

31. Describe the effects of physical exercise on the musculoskeletal system.

32. Explain the changes in the musculoskeletal system with aging and methods to prevent them.

33. Describe the embryological development of the skeletal system.

34. Explain the sexual dimorphism in the human skeletal system.

35. Describe the adaptation of human skeleton for bipedal locomotion.

36. Explain the biomechanics of human movement, including levers and muscle mechanics.

37. Describe the role of proprioception and balance in coordinated movement.

38. Explain the neural control of voluntary movement, including the role of motor cortex.

39. Describe the reflex mechanisms involved in posture and movement.

40. Explain the role of the cerebellum in motor coordination and learning.

41. Describe the spinal mechanisms controlling locomotion and reflexes.

42. Explain the development of motor skills from infancy to adulthood.

43. Describe the common injuries of the musculoskeletal system and their prevention.

44. Explain the principles of rehabilitation after musculoskeletal injuries.

45. Describe the use of prosthetics and orthotics in musculoskeletal disorders.

46. Explain the role of physical therapy in musculoskeletal health.

47. Describe the impact of lifestyle factors on musculoskeletal health.

48. Explain the genetic disorders affecting the musculoskeletal system.

49. Describe the autoimmune conditions affecting muscles and joints.

50. Explain the metabolic disorders affecting bone and muscle health.

51. Describe the structure and function of tendons and ligaments in detail.

52. Explain the healing process of soft tissue injuries in the musculoskeletal system.

53. Describe the role of inflammation in musculoskeletal disorders and healing.

54. Explain the pharmacological treatment of musculoskeletal disorders.

55. Describe the surgical interventions for musculoskeletal problems.

56. Explain the biomechanics of common sports injuries and their prevention.

57. Describe the adaptations of the musculoskeletal system to different types of physical training.

58. Explain the role of nutrition in athletic performance and muscle development.

59. Describe the gender differences in muscle strength and skeletal structure.

60. Explain the hormonal influences on muscle and bone development.

61. Describe the calcium homeostasis and its regulation in relation to bone health.

62. Explain the vitamin D metabolism and its importance for musculoskeletal health.

63. Describe the role of parathyroid hormone in calcium and phosphate regulation.

64. Explain the function of calcitonin in bone metabolism.

65. Describe the growth hormone effects on musculoskeletal development.

66. Explain the role of thyroid hormones in bone and muscle metabolism.

67. Describe the effects of sex hormones on bone density and muscle mass.

68. Explain the impact of cortisol on musculoskeletal tissues.

69. Describe the molecular basis of muscle hypertrophy and atrophy.

70. Explain the satellite cells and muscle regeneration.

71. Describe the fiber type composition of different muscles and its functional significance.

72. Explain the energy metabolism in different types of muscle fibers.

73. Describe the lactate production and clearance during exercise.

74. Explain the concept of VO2 max and its relationship to muscle function.

75. Describe the cardiovascular adaptations to support muscle function during exercise.

76. Explain the respiratory adaptations during intense muscular activity.

77. Describe the thermoregulation mechanisms during prolonged muscle activity.

78. Explain the electrolyte balance and its importance in muscle function.

79. Describe the hydration requirements for optimal musculoskeletal function.

80. Explain the role of massage and manual therapy in musculoskeletal health.

81. Describe the biomechanical analysis of human gait and its clinical significance.

82. Explain the postural abnormalities and their impact on musculoskeletal health.

83. Describe the ergonomic principles in preventing musculoskeletal disorders.

84. Explain the occupational factors affecting musculoskeletal health.

85. Describe the role of genetics in determining muscle fiber composition.

86. Explain the epigenetic factors influencing musculoskeletal development.

87. Describe the stem cell therapy applications in musculoskeletal medicine.

88. Explain the tissue engineering approaches for musculoskeletal repair.

89. Describe the role of growth factors in muscle and bone regeneration.

90. Explain the molecular mechanisms of muscle protein synthesis.

91. Describe the autophagy and protein degradation pathways in muscles.

92. Explain the mitochondrial function in muscle energy metabolism.

93. Describe the oxidative stress and antioxidant mechanisms in muscles.

94. Explain the role of mechanical loading in bone and muscle adaptation.

95. Describe the microgravity effects on the musculoskeletal system.

96. Explain the comparative anatomy of locomotion in different vertebrates.

97. Describe the evolutionary adaptations of the human musculoskeletal system.

98. Explain the biomimetic applications inspired by animal locomotion.

99. Describe the future directions in musculoskeletal research and therapy.

100. Explain the integration of technology in musculoskeletal assessment and treatment.

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Answer Key Guidelines

Section A: Multiple Choice Questions - Answers

1. c) Movement of leucocytes
2. b) Sarcomere
3. a) 22 (8 cranium + 14 facial)
4. b) I-band
5. c) Synovial joints
6. b) 26
7. c) Neuromuscular junction
8. a) Clavicle and scapula
9. c) Acetylcholine
10. b) Paramecium
11. c) H-zone
12. c) 12
13. c) Estrogen
14. b) Hinge joint
15. c) Striated and involuntary
16. a) Malleus, incus, stapes
17. b) Uric acid crystals
18. c) Pectoral girdle
19. c) Internal organs
20. c) Sarcomere
21. c) 11th-12th pairs
22. c) Calcium
23. c) Saddle joint
24. b) Calcium ions
25. c) Femur
26. c) Euglena
27. a) A-band
28. b) 7
29. b) Inflammation of joints
30. b) Ball and socket joint
31. c) Multinucleated
32. c) Limbs and girdles
33. c) Actin and myosin
34. c) 12
35. c) Pivot joint
36. b) Multinucleated cell
37. b) 5
38. c) H-zone
39. c) Fibrous joints
40. b) I-band
41. b) Axial skeleton
42. a) Bones of fingers and toes
43. b) ATP
44. b) Two coxal bones
45. b) Thin filament
46. a) 5
47. c) Kneecap
48. b) Muscle relaxation
49. a) 1st-7th pairs
50. b) On the ventral midline
51. a) Sarcomeres
52. b) 7
53. a) Sarcolemma
54. b) 8th-10th pairs
55. b) Ball and socket joint
56. b) Cross-bridges
57. c) 8
58. c) Myosin pulling actin
59. a) 1 fused
60. b) Hinge joint
61. b) Muscle bundles
62. d) Lower leg
63. c) Actin
64. a) 1 fused (actually 5 fused vertebrae form the sacrum)
65. c) Gliding joints
66. b) Sarcoplasm
67. b) Forearm
68. b) Cross-bridge detachment
69. b) 14
70. b) Shin bone
71. b) Thin filament
72. a) 8 bones
73. b) Forearm
74. b) Calcium is removed
75. b) Foot
76. c) Sarcoplasmic reticulum
77. b) Upper arm
78. b) ATP
79. c) 14
80. b) Neuron and muscle
81. c) Streaming protoplasm
82. b) Appendicular skeleton
83. a) Only actin
84. b) 30
85. c) Neural signal
86. b) Shoulder to trunk
87. c) Mostly myosin
88. b) 30
89. b) Lack of ATP
90. a) 1
91. a) Voluntary and striated
92. b) Hip joint
93. c) Muscle contraction
94. b) Shoulder joint
95. c) Troponin
96. c) Spinal cord
97. b) Myosin
98. a) Heart and lungs
99. b) Muscle shortening
100. c) Brain

Section B: One Mark Short Questions - Answers

1. Define locomotion. The movement of an organism from one place to another.

2. What is amoeboid movement? Movement by pseudopodia formed by the streaming of protoplasm.

3. Name the protein filaments in sarcomere. Actin (thin filament) and Myosin (thick filament).

4. How many bones are in the human skull? 22 (8 cranial + 14 facial).

5. What is the functional unit of muscle? Sarcomere.

6. Define movement. The change in position of a part of the body relative to its axis.

7. Give an example of ciliary movement. Movement of the ovum in the fallopian tubes.

8. What is the axial skeleton? The part of the skeleton that consists of the skull, vertebral column, sternum, and ribs.

9. Name the neurotransmitter at neuromuscular junction. Acetylcholine.

10. What causes tetany? Low levels of Ca²⁺ in the body fluid.

11. Define sarcomere. The functional unit of muscle contraction, located between two successive Z-lines.

12. How many ribs are there in humans? 12 pairs.

13. What is myasthenia gravis? An autoimmune disorder affecting the neuromuscular junction.

14. Name the components of pectoral girdle. Clavicle and Scapula.

15. What is the I-band? The lighter band in a sarcomere that contains only actin filaments.

16. Define arthritis. Inflammation of joints.

17. Give an example of flagellar movement. Movement of spermatozoa.

18. What is osteoporosis? An age-related disorder characterized by decreased bone mass.

19. Name the ear ossicles. Malleus, Incus, and Stapes.

20. What is the H-zone? The central part of the A-band, where only myosin is present.

21. Define gout. Inflammation of joints due to the accumulation of uric acid crystals.

22. How many vertebrae are in vertebral column? 26.

23. What is sarcoplasm? The cytoplasm of a muscle fiber.

24. Name the types of ribs. True ribs, False ribs, and Floating ribs.

25. What is a syncytium? A multinucleated cell.

26. Define appendicular skeleton. The part of the skeleton that consists of the bones of the limbs and their girdles.

27. What is the A-band? The darker band in a sarcomere that contains myosin filaments.

28. How many cervical vertebrae are there? 7.

29. What is cross-bridge? The connection formed when myosin heads bind to actin filaments.

30. Name the components of pelvic girdle. Two coxal bones.

31. What is Z-line? A line that bisects the I-band and marks the boundary of a sarcomere.

32. How many thoracic vertebrae are present? 12.

33. Define fascicle. A bundle of muscle fibers.

34. What is M-line? A line that bisects the H-zone.

35. How many lumbar vertebrae are there? 5.

36. What is sarcolemma? The plasma membrane of a muscle fiber.

37. Name the longest bone in human body. Femur.

38. What is sarcoplasmic reticulum? The endoplasmic reticulum of a muscle fiber.

39. How many pairs of floating ribs are there? 2 pairs (11th and 12th).

40. Define myofibril. A contractile filament within a muscle cell, composed of sarcomeres.

41. What is patella? The kneecap.

42. How many metacarpals are in one hand? 5.

43. What is troponin? A protein on actin filaments that binds Ca²⁺.

44. Name the bones of forearm. Radius and Ulna.

45. What is tropomyosin? A protein on actin filaments that covers the myosin-binding sites.

46. How many phalanges are in one hand? 14.

47. Define power stroke. The step in muscle contraction where the myosin head pulls the actin filament.

48. What is acetabulum? The socket in the pelvic girdle that articulates with the head of the femur.

49. How many carpals are in one hand? 8.

50. What is glenoid cavity? The socket in the pectoral girdle that articulates with the head of the humerus.

51. How many tarsals are in one foot? 7.

52. Define rigor mortis. The stiffening of muscles after death due to the lack of ATP.

53. What is clavicle? The collarbone.

54. How many metatarsals are in one foot? 5.

55. What is scapula? The shoulder blade.

56. Name the thigh bone. Femur.

57. What is fibula? The smaller of the two bones in the lower leg.

58. Name the shin bone. Tibia.

59. What is humerus? The bone of the upper arm.

60. Name the bones of upper arm. Humerus.

61. What is radius? The shorter of the two bones in the forearm, on the thumb side.

62. Name the kneecap. Patella.

63. What is ulna? The longer of the two bones in the forearm, on the pinky side.

64. How many bones are in cranium? 8.

65. What is sternum? The breastbone.

66. How many facial bones are there? 14.

67. Define hyoid bone. A U-shaped bone in the neck that supports the tongue.

68. What causes osteoporosis? Decreased bone mass, often due to low estrogen levels.

69. Name the calf bone. Fibula.

70. What is the function of calcium in muscle contraction? It binds to troponin, exposing the myosin-binding sites on actin.

71. Define neuromuscular junction. The synapse between a motor neuron and a muscle fiber.

72. What is the role of ATP in muscle contraction? It provides energy for the power stroke and for detaching the myosin head from actin.

73. Name the three types of muscles. Skeletal, Smooth, and Cardiac.

74. What is the difference between movement and locomotion? Movement is a change in position of a body part; locomotion is the movement of the whole organism from one place to another.

75. Define joint. A point of articulation between two or more bones.

76. What are sutures? Immovable fibrous joints in the skull.

77. Name the movable joints. Synovial joints.

78. What is ball and socket joint? A synovial joint where a ball-shaped end of one bone fits into a cup-like socket of another (e.g., shoulder).

79. Give example of hinge joint. Knee joint, elbow joint.

80. What is pivot joint? A synovial joint that allows rotational movement (e.g., between atlas and axis vertebrae).

81. Define gliding joint. A synovial joint that allows sliding or gliding movements (e.g., between carpals).

82. What is saddle joint? A synovial joint with saddle-shaped articulating surfaces (e.g., thumb).

83. Name the immovable joints. Fibrous joints.

84. What are cartilaginous joints? Joints where bones are joined by cartilage, allowing limited movement.

85. Define synovial joints. Freely movable joints characterized by a synovial cavity.

86. What is synovial fluid? The lubricating fluid found in synovial joints.

87. Name the voluntary muscles. Skeletal muscles.

88. What are involuntary muscles? Smooth and cardiac muscles.

89. Define striated muscles. Muscles with a striped appearance due to the arrangement of sarcomeres (skeletal and cardiac).

90. What are non-striated muscles? Muscles without a striped appearance (smooth muscles).

91. Where are cardiac muscles found? In the heart.

92. What is the function of skeleton? To provide support, protection, and allow for movement.

93. Define bone. A rigid connective tissue that makes up the skeleton.

94. What is cartilage? A flexible connective tissue found in various parts of the body.

95. Name the hardest tissue in body. Bone (enamel is the hardest substance).

96. What is bone marrow? The soft tissue inside bones where blood cells are produced.

97. Define fracture. A break in a bone.

98. What is dislocation? The displacement of bones at a joint.

99. Name the smallest bone in human body. Stapes (in the ear).

100. What is the function of ribs? To protect the heart and lungs.

Section C: Two Marks Questions - Answers

1. Differentiate between movement and locomotion with examples.

   • Movement: The change in position of a part of the body. Example: Blinking of eyes.
   • Locomotion: The movement of the entire organism from one place to another. Example: Walking.

2. Describe amoeboid movement with examples. Amoeboid movement is a crawling-like movement facilitated by pseudopodia, which are formed by the streaming of protoplasm. Examples include Amoeba, macrophages, and leucocytes.

3. Explain ciliary movement and give two examples. Ciliary movement is the coordinated movement of cilia, which are hair-like projections. This movement helps in locomotion or in moving substances. Examples: Paramecium uses cilia for locomotion, and cilia in the trachea move dust particles.

4. What is flagellar movement? Give examples. Flagellar movement is a whip-like movement of one or more flagella, which are longer than cilia. It is primarily used for locomotion. Examples: Euglena and spermatozoa.

5. List the components of axial skeleton. The axial skeleton consists of the skull, vertebral column, sternum, and ribs.

6. Describe the structure of skull mentioning number of bones. The skull is composed of 22 bones, divided into the cranium (8 bones that protect the brain) and the facial bones (14 bones that form the front of the skull).

7. Explain the composition of vertebral column. The vertebral column is composed of 26 serially arranged vertebrae. It includes 7 cervical, 12 thoracic, 5 lumbar, 1 fused sacral, and 1 fused coccygeal vertebra.

8. What are the different types of ribs? Mention their numbers.

   • True ribs: First 7 pairs, attached directly to the sternum.
   • False ribs: 8th, 9th, and 10th pairs, attached to the 7th rib.
   • Floating ribs: 11th and 12th pairs, not attached to the sternum.

9. List the components of appendicular skeleton. The appendicular skeleton consists of the bones of the limbs (upper and lower) and their girdles (pectoral and pelvic).

10. Describe the pectoral girdle and its function. The pectoral girdle consists of the clavicle (collarbone) and the scapula (shoulder blade). Its function is to connect the upper limb to the axial skeleton.

11. Explain the structure of pelvic girdle. The pelvic girdle consists of two coxal bones, each formed by the fusion of three bones: ilium, ischium, and pubis. It connects the lower limb to the axial skeleton.

12. List the bones of upper limb with their numbers. Humerus (1), Radius (1), Ulna (1), Carpals (8), Metacarpals (5), and Phalanges (14).

13. Name the bones of lower limb with their numbers. Femur (1), Patella (1), Tibia (1), Fibula (1), Tarsals (7), Metatarsals (5), and Phalanges (14).

14. Differentiate between axial and appendicular skeleton.

    • Axial Skeleton: Forms the central axis of the body (skull, vertebrae, ribs, sternum).
    • Appendicular Skeleton: Consists of the limbs and girdles, attached to the axial skeleton.

15. What are joints? Classify them based on movement. Joints are points of articulation between bones. Based on movement, they are classified as:

    • Fibrous Joints: Immovable.
    • Cartilaginous Joints: Slightly movable.
    • Synovial Joints: Freely movable.

16. Describe fibrous joints with examples. Fibrous joints are immovable joints where bones are held together by dense fibrous connective tissue. Example: Sutures in the skull.

17. Explain cartilaginous joints with examples. Cartilaginous joints are slightly movable joints where bones are joined by cartilage. Example: Joints between adjacent vertebrae.

18. What are synovial joints? Give examples. Synovial joints are freely movable joints characterized by a fluid-filled synovial cavity between the articulating bones. Examples: Shoulder joint, knee joint.

19. Differentiate between ball and socket joint and hinge joint.

    • Ball and Socket Joint: Allows movement in all directions (e.g., shoulder).
    • Hinge Joint: Allows movement in one plane, like a door hinge (e.g., knee).

20. Compare skeletal, smooth, and cardiac muscles.

    • Skeletal: Striated, voluntary, attached to bones.
    • Smooth: Non-striated, involuntary, in internal organs.
    • Cardiac: Striated, involuntary, in the heart.

21. Describe the structure of skeletal muscle fiber. A skeletal muscle fiber is a long, cylindrical, multinucleated cell (syncytium). It contains sarcoplasm, a sarcoplasmic reticulum, and numerous myofibrils.

22. What is sarcomere? Explain its components. A sarcomere is the functional unit of a myofibril. It consists of overlapping actin (thin) and myosin (thick) filaments, bounded by Z-lines. It includes A-bands, I-bands, and an H-zone.

23. Differentiate between actin and myosin filaments.

    • Actin (Thin Filament): Composed of actin, troponin, and tropomyosin proteins. Forms the I-band.
    • Myosin (Thick Filament): Composed of myosin protein with a head and a tail. Forms the A-band.

24. Explain the banding pattern of sarcomere. The sarcomere has a distinct banding pattern: the dark A-band (myosin and actin overlap), the light I-band (actin only), the H-zone in the center of the A-band (myosin only), and the M-line in the middle of the H-zone.

25. What is the role of calcium in muscle contraction? Calcium ions (Ca²⁺) bind to troponin on the actin filaments. This causes a conformational change that exposes the myosin-binding sites on actin, allowing cross-bridges to form.

26. Describe the neuromuscular junction. The neuromuscular junction is the synapse between a motor neuron and a skeletal muscle fiber. It is where the nerve impulse is transmitted to the muscle, initiating contraction.

27. Explain the role of acetylcholine in muscle contraction. Acetylcholine is a neurotransmitter released at the neuromuscular junction. It binds to receptors on the sarcolemma, generating an action potential that triggers muscle contraction.

28. What happens during the power stroke? During the power stroke, the myosin head, bound to actin, pivots and pulls the actin filament toward the center of the sarcomere (M-line). This movement is powered by the hydrolysis of ATP.

29. Describe muscle relaxation process. Muscle relaxation occurs when the neural signal stops. Calcium ions are pumped back into the sarcoplasmic reticulum, troponin returns to its original shape, tropomyosin covers the actin binding sites, and the muscle fiber lengthens.

30. What is cross-bridge cycle? The cross-bridge cycle is the repeated sequence of events where myosin heads bind to actin, perform a power stroke, detach, and then re-cock for the next cycle. This process continues as long as calcium and ATP are present.

31. Explain the role of ATP in muscle contraction. ATP has two main roles in muscle contraction: its hydrolysis provides the energy for the power stroke, and its binding to the myosin head causes the detachment of the cross-bridge from actin.

32. What are the symptoms of myasthenia gravis? Myasthenia gravis is an autoimmune disorder that causes fatigue, weakening, and paralysis of skeletal muscles. It affects the neuromuscular junction.

33. Describe tetany and its cause. Tetany is a condition characterized by rapid, involuntary muscle spasms (wild contractions). It is caused by low levels of calcium (Ca²⁺) in the body fluid.

34. What is arthritis? Mention its types. Arthritis is the inflammation of one or more joints. Common types include osteoarthritis (degenerative) and rheumatoid arthritis (autoimmune).

35. Explain osteoporosis and its causes. Osteoporosis is an age-related disorder characterized by decreased bone mass and increased risk of fractures. It is commonly caused by decreased levels of estrogen, particularly in post-menopausal women.

36. What is gout? Describe its symptoms. Gout is a form of arthritis caused by the accumulation of uric acid crystals in the joints. It leads to severe pain, redness, and swelling, often in the big toe.

37. Compare true ribs, false ribs, and floating ribs.

    • True Ribs (1-7): Attach directly to the sternum via their own costal cartilage.
    • False Ribs (8-10): Their costal cartilages are attached to the cartilage of the 7th rib, not directly to the sternum.
    • Floating Ribs (11-12): Do not attach to the sternum at all.

38. Describe the structure and function of sternum. The sternum, or breastbone, is a flat bone located in the anterior midline of the chest. It consists of three parts: the manubrium, body, and xiphoid process. Its primary function is to protect the heart and lungs and to serve as an attachment point for the ribs and clavicles.

39. What are the functions of skeletal system? The skeletal system provides structural support, protects vital organs, allows for movement through muscle attachment, stores minerals (like calcium), and is the site of blood cell formation (hematopoiesis).

40. Explain the difference between bone and cartilage.

    • Bone: A hard, rigid connective tissue with a calcified matrix. It is highly vascular and provides the main structural framework of the body.
    • Cartilage: A flexible, avascular connective tissue with a rubbery matrix. It provides support and cushioning in joints and other areas.

41. What is the significance of synovial fluid? Synovial fluid is a viscous fluid found in synovial joints. Its significance lies in lubricating the joint to reduce friction between the articular cartilages, absorbing shocks, and nourishing the cartilage cells.

42. Describe the structure of synovial joint. A synovial joint is characterized by a synovial cavity filled with fluid. It is enclosed by a fibrous joint capsule lined with a synovial membrane. The ends of the articulating bones are covered with smooth articular cartilage to reduce friction.

43. What are the types of movements possible at joints? Joints allow for various types of movements, including gliding (sliding), angular movements (flexion, extension, abduction, adduction), and rotational movements (rotation, circumduction).

44. Explain flexion and extension movements.

    • Flexion: A movement that decreases the angle between two body parts. Example: Bending the elbow.
    • Extension: A movement that increases the angle between two body parts, straightening it. Example: Straightening the knee.

45. What is abduction and adduction?

    • Abduction: Movement of a limb away from the midline of the body. Example: Lifting the arm out to the side.
    • Adduction: Movement of a limb toward the midline of the body. Example: Bringing the arm back to the side.

46. Describe rotation and circumduction movements.

    • Rotation: Movement of a bone around its own long axis. Example: Turning the head from side to side.
    • Circumduction: A circular movement of a limb, creating a cone shape. It is a combination of flexion, extension, abduction, and adduction. Example: Circling the arm.

47. What is the function of ligaments? Ligaments are strong, fibrous bands of connective tissue that connect bone to bone. Their primary function is to stabilize and support joints, preventing excessive or abnormal movements.

48. Explain the role of tendons. Tendons are tough, flexible bands of fibrous connective tissue that connect muscle to bone. Their role is to transmit the force generated by muscle contraction to the bone, thereby producing movement.

49. What are the characteristics of skeletal muscles? Skeletal muscles are striated (have a striped appearance), under voluntary control, and are typically attached to bones. They are responsible for locomotion and all voluntary movements of the body.

50. Describe the properties of smooth muscles. Smooth muscles are non-striated, involuntary muscles found in the walls of internal organs like the stomach, intestines, and blood vessels. They are responsible for processes like peristalsis and regulating blood pressure.

51. What are the features of cardiac muscles? Cardiac muscles are found only in the heart. They are striated, like skeletal muscles, but are involuntary. They have intercalated discs that connect the cells, allowing for synchronized contraction of the heart.

52. Explain voluntary and involuntary muscles.

    • Voluntary Muscles: Muscles that are under conscious control. Skeletal muscles are the primary example.
    • Involuntary Muscles: Muscles that are not under conscious control. Smooth and cardiac muscles are examples.

53. What is the difference between striated and non-striated muscles?

    • Striated Muscles: Have a striped or banded appearance under a microscope due to the regular arrangement of sarcomeres (e.g., skeletal and cardiac muscle).
    • Non-striated Muscles: Lack this banded appearance because their contractile proteins are not arranged in sarcomeres (e.g., smooth muscle).

54. Describe the microscopic structure of skeletal muscle. A skeletal muscle is composed of bundles of muscle fibers called fascicles. Each muscle fiber is a single, long, multinucleated cell containing myofibrils, which are made of repeating contractile units called sarcomeres.

55. What is the role of sarcoplasmic reticulum? The sarcoplasmic reticulum is a specialized type of smooth endoplasmic reticulum found in muscle cells. Its primary role is to store and release calcium ions (Ca²⁺), which are essential for initiating muscle contraction.

56. Explain the function of T-tubules. T-tubules (transverse tubules) are invaginations of the sarcolemma that penetrate deep into the muscle cell. Their function is to conduct the action potential from the cell surface to the sarcoplasmic reticulum, ensuring a rapid and coordinated release of calcium throughout the muscle fiber.

57. What is excitation-contraction coupling? Excitation-contraction coupling is the process by which a neural stimulus (excitation) triggers a muscle contraction. It involves the action potential traveling down the T-tubules, leading to calcium release from the sarcoplasmic reticulum and the subsequent interaction of actin and myosin.

58. Describe the sliding filament mechanism. The sliding filament mechanism is the process of muscle contraction where the thin (actin) filaments slide past the thick (myosin) filaments. This sliding action pulls the Z-lines closer together, shortening the sarcomere and thus the entire muscle.

59. What happens during muscle fatigue? Muscle fatigue is the decline in the ability of a muscle to generate force. It can be caused by a variety of factors, including the accumulation of lactic acid, depletion of ATP and glycogen stores, and ionic imbalances.

60. Explain oxygen debt in muscles. Oxygen debt (now more commonly referred to as EPOC - Excess Post-exercise Oxygen Consumption) is the extra oxygen the body needs after strenuous exercise to restore metabolic conditions to the resting level. This includes converting lactic acid back to glucose and replenishing ATP and creatine phosphate stores.

61. What is the all-or-none law of muscle contraction? The all-or-none law states that an individual muscle fiber will contract to its fullest extent or not at all in response to a stimulus. If the stimulus is strong enough to reach the threshold, the fiber will contract completely.

62. Describe isotonic and isometric contractions.

    • Isotonic Contraction: The muscle changes length while the tension remains constant. Example: Lifting a weight.
    • Isometric Contraction: The muscle develops tension but does not change in length. Example: Pushing against an immovable wall.

63. What is muscle tone? Muscle tone is the continuous and passive partial contraction of the muscles, or the muscle's resistance to passive stretch during the resting state. It helps maintain posture and keeps muscles ready for action.

64. Explain motor unit. A motor unit consists of a single motor neuron and all the muscle fibers it innervates. The size of a motor unit varies; fine control muscles (like in the eye) have small motor units, while large weight-bearing muscles (like the quadriceps) have large motor units.

65. What is the role of motor neuron in muscle contraction? A motor neuron transmits the nerve impulse from the central nervous system to the muscle fibers. The release of the neurotransmitter acetylcholine from the motor neuron at the neuromuscular junction initiates the action potential that leads to muscle contraction.

66. Describe the graded response in muscles. A graded response refers to the ability of a whole muscle to contract with varying degrees of force. This is achieved by changing the frequency of stimulation of muscle fibers and by recruiting a varying number of motor units.

67. What is summation in muscle contraction? Summation is the process where the force of a second muscle contraction is added to the first if it occurs before the muscle has fully relaxed. This results in a stronger, more sustained contraction.

68. Explain tetanus in muscle physiology. Tetanus (or tetanic contraction) is a sustained muscle contraction that occurs when the frequency of stimulation is so high that the muscle has no time to relax between stimuli. This results in a smooth, continuous contraction, which is how most voluntary movements are produced.

69. What are fast and slow twitch muscle fibers?

    • Slow-twitch (Type I): Contract slowly, are resistant to fatigue, and are rich in myoglobin and mitochondria. They are used for endurance activities like long-distance running.
    • Fast-twitch (Type II): Contract quickly and powerfully but fatigue rapidly. They are used for short, explosive movements like sprinting.

70. Describe the energy sources for muscle contraction. The immediate source of energy for muscle contraction is ATP. Muscles have a small store of ATP, which is quickly replenished by three main systems: the creatine phosphate system (for short bursts), anaerobic glycolysis (for intermediate activity), and aerobic respiration (for sustained activity).

71. What is creatine phosphate system? The creatine phosphate system is a rapid way to generate ATP. Creatine phosphate stored in the muscle donates a phosphate group to ADP to form ATP. This provides energy for the first few seconds of intense muscular activity.

72. Explain anaerobic glycolysis in muscles. Anaerobic glycolysis is the breakdown of glucose to pyruvic acid (and then to lactic acid) without the use of oxygen. It provides a rapid supply of ATP for short-term, high-intensity exercise when oxygen delivery is insufficient.

73. What is the role of myoglobin in muscles? Myoglobin is an oxygen-storing protein found in muscle cells, particularly abundant in slow-twitch fibers. It acts as a local oxygen reserve, releasing oxygen when the demand is high, thus facilitating aerobic respiration.

74. Describe muscle hypertrophy and atrophy.

    • Hypertrophy: An increase in the size of muscle fibers, and thus the muscle as a whole, typically in response to resistance training.
    • Atrophy: A decrease in the size of muscle fibers, and thus the muscle as a whole, due to disuse, denervation, or disease.

75. What are the effects of exercise on muscles? Regular exercise leads to several adaptations in muscles. Aerobic exercise improves endurance by increasing mitochondria and blood supply. Resistance exercise leads to hypertrophy, increasing muscle strength and size.

76. Explain the importance of warm-up before exercise. Warming up before exercise increases muscle temperature and blood flow. This improves muscle elasticity, enhances the speed of nerve impulses, and increases the rate of energy production, which helps to improve performance and reduce the risk of injury.

77. What causes muscle cramps? Muscle cramps are sudden, involuntary, and painful contractions of a muscle. They can be caused by dehydration, electrolyte imbalances (e.g., low potassium or calcium), muscle fatigue, or nerve irritation.

78. Describe the healing process of bone fractures. Bone healing is a multi-stage process. First, a hematoma (blood clot) forms at the fracture site. This is followed by the formation of a fibrocartilaginous callus, which is then converted into a bony callus. Finally, the bony callus is remodeled into mature bone tissue.

79. What is the role of calcium and phosphorus in bones? Calcium and phosphorus are the primary minerals that make up the inorganic matrix of bone, forming hydroxyapatite crystals. These minerals give bones their hardness and rigidity, making them strong and supportive.

80. Explain the importance of vitamin D for bones. Vitamin D is essential for bone health because it facilitates the absorption of calcium from the small intestine into the bloodstream. Without sufficient vitamin D, the body cannot effectively absorb calcium, which can lead to weak and brittle bones (osteoporosis or rickets).

81. What are the effects of aging on skeletal system? With aging, bone density tends to decrease (osteoporosis), making bones more brittle and susceptible to fractures. Cartilage in joints can wear down, leading to osteoarthritis, and ligaments may become less elastic, reducing flexibility.

82. Describe the gender differences in skeletal system. The male skeleton is generally larger and heavier than the female skeleton. The female pelvis is typically wider and shallower than the male pelvis to facilitate childbirth. These differences are primarily influenced by sex hormones.

83. What is the role of hormones in bone development? Several hormones regulate bone development. Growth hormone stimulates bone growth during childhood. Thyroid hormones promote bone formation. Sex hormones (estrogen and testosterone) are crucial for bone growth during puberty and for maintaining bone mass in adults.

84. Explain the process of ossification. Ossification is the process of bone formation. There are two types: intramembranous ossification (where bone develops from a fibrous membrane, e.g., flat bones of the skull) and endochondral ossification (where bone replaces a hyaline cartilage model, e.g., long bones).

85. What are growth plates in bones? Growth plates, or epiphyseal plates, are areas of hyaline cartilage located at the ends of long bones in children and adolescents. They are the sites where longitudinal bone growth occurs. They close (ossify) at the end of puberty.

86. Describe the blood supply to bones. Bones are highly vascular tissues. They receive blood from nutrient arteries that enter the bone shaft, as well as from periosteal and epiphyseal arteries. This blood supply is essential for delivering nutrients, oxygen, and hormones, and for removing waste products.

87. What is the lymphatic drainage of bones? Bones have a network of lymphatic vessels, primarily located in the periosteum. These vessels are important for draining interstitial fluid, immune surveillance, and are also implicated in the process of bone remodeling and repair.

88. Explain the innervation of skeletal muscles. Skeletal muscles are innervated by motor neurons, which transmit signals from the central nervous system to cause contraction. They also contain sensory neurons that provide feedback to the CNS about muscle length and tension (proprioception).

89. What are the postural muscles? Postural muscles are muscles that are responsible for maintaining the body's posture against gravity. They are typically dominated by slow-twitch muscle fibers and are in a constant state of low-level contraction (muscle tone). Examples include the muscles of the back and neck.

90. Describe the muscles of facial expression. The muscles of facial expression are a group of skeletal muscles that insert into the skin of the face. Their contraction produces various facial expressions, such as smiling, frowning, and raising the eyebrows. They are innervated by the facial nerve.

91. What are the muscles of mastication? The muscles of mastication are the four muscles responsible for chewing. They are the temporalis, masseter, and medial and lateral pterygoids. They act on the mandible (lower jaw) to produce movements like elevation, depression, protraction, and retraction.

92. Explain the respiratory muscles. The primary respiratory muscles are the diaphragm and the intercostal muscles. The diaphragm is a large, dome-shaped muscle that contracts to increase the volume of the thoracic cavity during inhalation. The intercostal muscles, located between the ribs, also assist in changing the volume of the chest cavity.

93. What are the core muscles? The core muscles are the group of muscles in the trunk that stabilize the spine and pelvis. They include the abdominal muscles, muscles of the lower back, and the pelvic floor muscles. A strong core is essential for stability, balance, and posture.

94. Describe the limb muscles. Limb muscles are the muscles of the arms and legs. They are responsible for all movements of the limbs, such as walking, running, lifting, and grasping. They are organized into compartments that produce specific movements (e.g., flexors and extensors).

95. What is the role of proprioception in movement? Proprioception is the body's ability to sense its own position, motion, and equilibrium. Sensory receptors in muscles, tendons, and joints provide the central nervous system with continuous feedback, which is crucial for coordinated and accurate movement.

96. Explain balance and coordination. Balance is the ability to maintain the body's center of gravity over its base of support. Coordination is the ability to use different parts of the body together smoothly and efficiently. Both are complex processes involving the cerebellum, inner ear, and proprioceptive feedback.

97. What are reflexes in relation to movement? Reflexes are rapid, involuntary responses to a stimulus. In movement, they serve protective functions (e.g., the withdrawal reflex from a painful stimulus) and are also involved in maintaining posture and coordinating basic movement patterns like walking.

98. Describe the role of cerebellum in movement. The cerebellum plays a critical role in motor control. It does not initiate movement but contributes to its coordination, precision, and accurate timing. It receives sensory input and integrates it to fine-tune motor activity, and is also important for motor learning.

99. What is the motor cortex? The motor cortex is the region of the cerebral cortex involved in the planning, control, and execution of voluntary movements. The primary motor cortex is responsible for generating the neural impulses that control the execution of movement.

100. Explain the spinal control of movement. The spinal cord acts as more than just a relay station; it contains complex neural circuits called central pattern generators (CPGs) that can generate the rhythmic patterns of motor output needed for movements like walking, without direct input from the brain for each step. It also mediates various reflexes.

Section D: Three Marks Broad Questions - Answers

1. Describe the different types of movements in organisms with suitable examples and explain their significance.

   • Movement: Change in position of a body part.
   • Locomotion: Movement of an organism from one place to another.
   • Types:
     • Amoeboid: By pseudopodia (streaming protoplasm). E.g., Amoeba, macrophages, leucocytes. Significance: Phagocytosis, cell migration.
     • Ciliary: By cilia. E.g., Paramecium, in the trachea (dust removal), in the fallopian tubes (ovum movement). Significance: Particle clearance, gamete transport.
     • Flagellar: By flagella. E.g., Euglena, spermatozoa. Significance: Propulsion, reproduction.
     • Muscular: By muscles. Most common in higher animals. Significance: Complex movements, locomotion.

2. Give a detailed account of the human skeletal system, including its divisions and major components.

   • Definition: Framework of bones and cartilage for support, protection, and movement.
   • Divisions:
     • Axial Skeleton: Skull (cranium 8, facial 14, hyoid 1, ear ossicles 3 pairs), Vertebral Column (26 vertebrae: C7, T12, L5, S1 fused, Co1 fused), Sternum, Ribs (12 pairs: 1-7 true, 8-10 false, 11-12 floating).
     • Appendicular Skeleton: Limbs and girdles. Pectoral Girdle (clavicle, scapula), Pelvic Girdle (2 coxal bones). Upper Limb (Humerus, Radius, Ulna, Carpals 8, Metacarpals 5, Phalanges 14). Lower Limb (Femur, Patella, Tibia, Fibula, Tarsals 7, Metatarsals 5, Phalanges 14).

3. Explain the structure of human skull in detail, mentioning the number and names of bones in cranium and face.

   • Skull: Part of axial skeleton.
   • Cranium: 8 bones. Protects the brain.
   • Facial bones: 14 bones. Form the front part of the skull.
   • Also includes hyoid bone (1) and ear ossicles (Malleus, Incus, Stapes - 3 pairs).

4. Describe the vertebral column of humans, including the number, types, and functions of different vertebrae.

   • Vertebral Column: 26 serially arranged vertebrae.
   • Types & Numbers: Cervical (7), Thoracic (12), Lumbar (5), Sacral (1 fused), Coccygeal (1 fused).
   • Functions: Provides main support to the body, protects the spinal cord, serves as attachment point for ribs and muscles.

5. Give a comprehensive account of the appendicular skeleton, including the girdles and limb bones.

   • Appendicular Skeleton: Bones of limbs and their girdles.
   • Pectoral Girdle: Clavicle and Scapula. Connects upper limb to axial skeleton.
   • Pelvic Girdle: Two coxal bones. Connects lower limb to axial skeleton.
   • Upper Limb Bones: Humerus, Radius, Ulna, Carpals (8), Metacarpals (5), Phalanges (14).
   • Lower Limb Bones: Femur, Patella, Tibia, Fibula, Tarsals (7), Metatarsals (5), Phalanges (14).

6. Classify joints based on structure and function. Describe each type with suitable examples.

   • Definition: Articulation points between two or more bones, or between a bone and cartilage.
   • Types:
     • Fibrous Joints: No movement. E.g., Sutures in skull.
     • Cartilaginous Joints: Limited movement. Bones joined by cartilage. E.g., Between vertebrae.
     • Synovial Joints: Considerable movement, with synovial cavity. E.g., Ball and socket (shoulder, hip), Hinge (knee, elbow), Pivot (atlas/axis), Gliding (carpals), Saddle (thumb).

7. Explain the structure and function of synovial joints in detail with examples of different types.

   • Structure: Characterized by a fluid-filled synovial cavity between articulating bone surfaces. Articulating surfaces covered by articular cartilage. Joint capsule encloses the cavity.
   • Function: Allow considerable movement, reduce friction, absorb shock.
   • Examples:
     • Ball and socket: Shoulder, hip (multiaxial movement).
     • Hinge: Knee, elbow (flexion/extension).
     • Pivot: Atlas and axis (rotation).
     • Gliding: Carpals (sliding/gliding).
     • Saddle: Thumb (biaxial movement).

8. Describe the microscopic structure of skeletal muscle fiber, including all its components and their functions.

   • Skeletal Muscle Fibre (Cell): Multinucleated (syncytium).
   • Components:
     • Sarcoplasm: Cytoplasm of muscle fiber.
     • Sarcoplasmic Reticulum (SR): Endoplasmic reticulum, stores and releases Ca²⁺.
     • Sarcolemma: Plasma membrane of muscle fiber.
     • Myofibrils: Contractile units, composed of repeating sarcomeres.

9. Give a detailed explanation of the sarcomere structure and the arrangement of protein filaments.

   • Sarcomere: Functional unit of muscle contraction, region between two successive Z-lines.
   • Protein Filaments:
     • Actin (Thin Filament): Forms the lighter I-band.
     • Myosin (Thick Filament): Forms the darker A-band.
   • Banding Pattern:
     • I-band: Contains only actin filaments. Bisected by Z-line.
     • A-band: Contains myosin filaments, and overlapping actin filaments at ends.
     • H-zone: Central part of A-band, where only myosin is present. Bisected by M-line.
     • M-line: Bisects the H-zone.

10. Explain the sliding filament theory of muscle contraction step by step with molecular details.

    • Mechanism: Actin filaments slide over myosin filaments.
    • Steps:
      1. Neural Signal: CNS signal reaches neuromuscular junction.
      2. Neurotransmitter Release: Acetylcholine released, generating action potential on sarcolemma.
      3. Calcium Release: Action potential spreads, Ca²⁺ released from SR into sarcoplasm.
      4. Actin-Myosin Binding: Ca²⁺ binds to troponin, exposing myosin-binding sites on actin. Myosin heads form cross-bridges with actin.
      5. Power Stroke: Myosin head pulls actin towards M-line. ATP hydrolysis provides energy.
      6. Cross-Bridge Detachment: New ATP binds to myosin head, causing detachment.
      7. Myosin Head Re-cocking: ATP hydrolyzed, myosin head re-cocks for next cycle.
      8. Relaxation: Neural signal stops, Ca²⁺ pumped back into SR, myosin detaches, muscle relaxes.

11. Describe the role of calcium ions in muscle contraction and relaxation processes.

    • Contraction: Ca²⁺ released from sarcoplasmic reticulum. Binds to troponin on actin filaments, causing tropomyosin to move and expose myosin-binding sites on actin. This allows cross-bridge formation.
    • Relaxation: When neural signal stops, Ca²⁺ is actively pumped back into the sarcoplasmic reticulum. This removes Ca²⁺ from troponin, allowing tropomyosin to cover the myosin-binding sites on actin, preventing cross-bridge formation and leading to muscle relaxation.

12. Explain the events at the neuromuscular junction during muscle stimulation.

    • A neural signal (action potential) arrives at the axon terminal of a motor neuron.
    • This causes the release of the neurotransmitter acetylcholine into the synaptic cleft.
    • Acetylcholine binds to receptors on the sarcolemma (muscle fiber membrane).
    • This binding generates an action potential in the sarcolemma, initiating muscle contraction.

13. Give a detailed account of the cross-bridge cycle in muscle contraction.

    • Cross-Bridge Formation: Myosin heads, energized by ATP hydrolysis, bind to exposed active sites on actin filaments (after Ca²⁺ binds to troponin).
    • Power Stroke: The bound myosin head pivots, pulling the actin filament towards the M-line. ADP and Pi are released.
    • Cross-Bridge Detachment: A new ATP molecule binds to the myosin head, causing it to detach from the actin filament.
    • Myosin Head Re-cocking: The newly bound ATP is hydrolyzed into ADP and Pi, re-energizing and re-cocking the myosin head, preparing it for another cycle. This cycle continues as long as Ca²⁺ and ATP are available.

14. Describe the energy requirements and ATP utilization during muscle contraction and relaxation.

    • Contraction: ATP is hydrolyzed during the power stroke (myosin pulling actin) to provide energy for the movement.
    • Detachment: A new ATP molecule is required to bind to the myosin head to cause its detachment from actin.
    • Re-cocking: ATP hydrolysis re-energizes and re-cocks the myosin head.
    • Relaxation: ATP is required to actively pump Ca²⁺ back into the sarcoplasmic reticulum, which is crucial for muscle relaxation.

15. Explain the disorders of the muscular system: myasthenia gravis, tetany, and their causes.

    • Myasthenia Gravis: Autoimmune disorder affecting neuromuscular junction. Causes fatigue, weakening, and paralysis of skeletal muscles.
    • Tetany: Rapid spasms (wild contractions) in muscles. Caused by low Ca²⁺ levels in body fluid.

16. Describe the disorders of the skeletal system: arthritis, osteoporosis, and gout with their causes and symptoms.

    • Arthritis: Inflammation of joints. Symptoms include pain, swelling, stiffness.
    • Osteoporosis: Age-related disorder with decreased bone mass and increased fracture risk. Common cause is decreased estrogen levels. Symptoms include bone fragility, fractures.
    • Gout: Inflammation of joints due to accumulation of uric acid crystals. Symptoms include severe pain, redness, swelling in joints.

17. Compare and contrast the three types of muscles in terms of structure, location, and function.

    • Skeletal Muscles:
      • Structure: Striated, multinucleated (syncytium).
      • Location: Attached to bones.
      • Function: Voluntary movement, locomotion, posture.
    • Smooth Muscles:
      • Structure: Non-striated, uninucleated.
      • Location: Internal organs (e.g., digestive tract, blood vessels).
      • Function: Involuntary movements (e.g., peristalsis, vasoconstriction).
    • Cardiac Muscles:
      • Structure: Striated, uninucleated (or sometimes binucleated), branched, intercalated discs.
      • Location: Heart.
      • Function: Involuntary pumping of blood.

18. Explain the process of excitation-contraction coupling in skeletal muscles.

    • Excitation-contraction coupling is the sequence of events from the generation of an action potential in the sarcolemma to the initiation of muscle contraction.
    • It involves the neural signal leading to acetylcholine release at the neuromuscular junction, generating an action potential on the sarcolemma.
    • This action potential propagates along the sarcolemma and into the T-tubules, triggering the release of Ca²⁺ from the sarcoplasmic reticulum.
    • The released Ca²⁺ then binds to troponin, initiating the cross-bridge cycle and muscle contraction.

19. Describe the different types of muscle contractions: isotonic, isometric, and their physiological significance.

    • Isotonic Contraction: Muscle length changes while tension remains relatively constant. Used for movement.
      • Concentric: Muscle shortens (e.g., lifting a weight).
      • Eccentric: Muscle lengthens under tension (e.g., lowering a weight slowly).
    • Isometric Contraction: Muscle generates tension but its length remains constant. Used for maintaining posture or stabilizing joints. (e.g., holding a heavy object still).
    • Physiological Significance: Isotonic contractions are for dynamic movements, while isometric contractions are for static holding and stabilization. Both are essential for daily activities and exercise.

20. Explain muscle fatigue, its causes, and the recovery process including oxygen debt.

    • Muscle Fatigue: Decline in muscle's ability to generate force after prolonged activity.
    • Causes: Accumulation of lactic acid, depletion of ATP and glycogen, ionic imbalances (e.g., K+), central fatigue (nervous system).
    • Oxygen Debt: The extra amount of oxygen needed by the body after strenuous exercise to repay the oxygen deficit incurred during the activity. This oxygen is used to:
      • Convert lactic acid back to pyruvate/glucose.
      • Replenish ATP and creatine phosphate stores.
      • Replenish oxygen bound to myoglobin.
    • Recovery: Involves rest, adequate oxygen intake, and metabolic processes to restore muscle to its pre-fatigue state.

21. Describe the structure and function of the pectoral girdle and its articulations.

    • Structure: Consists of the clavicle (collarbone) and scapula (shoulder blade).
    • Function: Connects the upper limb to the axial skeleton, provides attachment for muscles that move the arm, and allows for a wide range of motion of the arm.
    • Articulations:
      • Scapula: Articulates with the humerus at the glenoid cavity (shoulder joint) and with the clavicle.
      • Clavicle: Articulates with the sternum medially and the scapula laterally.

22. Give a detailed account of the pelvic girdle, its components, and gender differences.

    • Components: Consists of two coxal bones (hip bones), which are fused from ilium, ischium, and pubis. These two coxal bones articulate with the sacrum posteriorly.
    • Function: Connects the lower limb to the axial skeleton, supports the weight of the upper body, protects pelvic organs.
    • Gender Differences:
      • Female Pelvis: Wider and shallower, larger pelvic inlet/outlet, wider subpubic angle (greater than 90 degrees), more circular pelvic brim. Adapted for childbirth.
      • Male Pelvis: Narrower and deeper, smaller pelvic inlet/outlet, narrower subpubic angle (less than 90 degrees), heart-shaped pelvic brim. Adapted for strength and support.

23. Explain the structure and functions of the rib cage, including the classification of ribs.

    • Structure: Formed by the thoracic vertebrae posteriorly, the sternum anteriorly, and the ribs laterally.
    • Functions: Protects vital organs (heart, lungs), provides attachment for respiratory muscles, aids in breathing movements.
    • Classification of Ribs (12 pairs):
      • True Ribs (1-7 pairs): Directly attach to the sternum via their own costal cartilages.
      • False Ribs (8-10 pairs): Do not directly attach to the sternum; their costal cartilages join the cartilage of the rib above.
      • Floating Ribs (11-12 pairs): Do not attach to the sternum or to other ribs anteriorly; they end freely in the abdominal musculature.

24. Describe the bones of the upper limb in detail, including their articulations and functions.

    • Humerus: Upper arm bone. Articulates with scapula (shoulder joint) and with radius and ulna (elbow joint). Function: Provides attachment for arm muscles, allows arm movement.
    • Radius: Forearm bone (thumb side). Articulates with humerus (elbow), ulna, and carpals (wrist). Function: Allows pronation and supination of forearm, supports hand.
    • Ulna: Forearm bone (pinky side). Articulates with humerus (elbow) and radius. Function: Forms major part of elbow joint, provides stability to forearm.
    • Carpals (8): Wrist bones. Articulate with radius and metacarpals. Function: Allow wrist movement.
    • Metacarpals (5): Palm bones. Articulate with carpals and phalanges. Function: Form the framework of the palm.
    • Phalanges (14): Finger bones (2 in thumb, 3 in other fingers). Articulate with metacarpals and other phalanges. Function: Allow grasping and fine motor movements.

25. Give a comprehensive account of the bones of the lower limb and their functional significance.

    • Femur: Thigh bone (longest and strongest). Articulates with pelvic girdle (hip joint) and patella/tibia (knee joint). Function: Supports body weight, allows locomotion.
    • Patella: Kneecap. Articulates with femur. Function: Protects knee joint, improves leverage of quadriceps muscle.
    • Tibia: Shin bone (larger lower leg bone). Articulates with femur (knee) and fibula/tarsals (ankle). Function: Bears body weight, provides stability.
    • Fibula: Calf bone (smaller lower leg bone). Articulates with tibia and tarsals. Function: Provides muscle attachment, stabilizes ankle.
    • Tarsals (7): Ankle bones. Articulate with tibia/fibula and metatarsals. Function: Form ankle joint, support foot arch.
    • Metatarsals (5): Foot bones. Articulate with tarsals and phalanges. Function: Form the arch of the foot, support body weight.
    • Phalanges (14): Toe bones (2 in big toe, 3 in other toes). Articulate with metatarsals and other phalanges. Function: Aid in balance, propulsion during walking.

26. Explain the development and growth of bones, including the role of growth plates and hormones.

    • Development (Ossification):
      • Intramembranous Ossification: Bone develops directly from mesenchymal connective tissue (e.g., flat bones of skull).
      • Endochondral Ossification: Bone replaces hyaline cartilage models (most bones).
    • Growth Plates (Epiphyseal Plates): Cartilaginous areas at the ends of long bones in children. Responsible for longitudinal bone growth. Chondrocytes proliferate and hypertrophy, then cartilage is replaced by bone. Fuse after puberty, stopping growth.
    • Hormones:
      • Growth Hormone: Stimulates overall bone growth.
      • Thyroid Hormones: Modulate activity of growth hormone, ensuring proper proportions.
      • Sex Hormones (Estrogen, Testosterone): Promote adolescent growth spurt and eventually cause closure of growth plates.
      • Parathyroid Hormone (PTH) & Calcitonin: Regulate calcium levels, influencing bone remodeling.
      • Vitamin D: Essential for calcium absorption and bone mineralization.

27. Describe the composition and properties of bone tissue, including compact and spongy bone.

    • Composition:
      • Organic Matrix (30-35%): Primarily collagen fibers and ground substance. Provides flexibility and tensile strength.
      • Inorganic Matrix (65-70%): Hydroxyapatite crystals (calcium phosphate) and other mineral salts. Provides hardness and compressional strength.
    • Properties: Strong, rigid, yet somewhat flexible. Highly vascularized and innervated.
    • Types:
      • Compact (Cortical) Bone: Dense, solid outer layer. Composed of osteons. Provides strength and protection.
      • Spongy (Cancellous/Trabecular) Bone: Lighter, porous inner layer. Composed of trabeculae with spaces filled with red bone marrow. Provides strength without excessive weight, resists stress from multiple directions.

28. Explain the process of bone remodeling and repair, including the role of osteoblasts and osteoclasts.

    • Bone Remodeling: Continuous process of bone resorption (removal of old bone) and bone deposition (formation of new bone).
      • Osteoclasts: Break down bone tissue.
      • Osteoblasts: Form new bone tissue.
    • Bone Repair (Fracture Healing):
      1. Hematoma Formation: Blood clot forms.
      2. Fibrocartilaginous Callus Formation: Fibrous tissue and cartilage form.
      3. Bony Callus Formation: Soft callus converted to spongy bone.
      4. Bone Remodeling: Bony callus remodeled to compact bone, restoring shape.

29. Describe the blood supply and innervation of bones and muscles.

    • Bones: Highly vascularized. Nutrient arteries supply compact bone, spongy bone, and marrow. Periosteal arteries supply outer compact bone. Innervated by sensory and sympathetic nerves.
    • Muscles: Richly supplied with blood vessels (arteries, veins, capillaries) for oxygen, nutrients, and waste removal. Skeletal muscles innervated by somatic motor neurons. Smooth and cardiac muscles by autonomic nervous system. Sensory nerves provide proprioception.

30. Explain the role of various nutrients and vitamins in maintaining healthy bones and muscles.

    • Bones: Calcium, Phosphorus (for structure); Vitamin D (Ca absorption); Vitamin K (bone protein); Vitamin C (collagen); Magnesium, Zinc.
    • Muscles: Protein (growth, repair); Carbohydrates, Fats (energy); Electrolytes (Na, K, Ca, Mg for function); B Vitamins (energy metabolism); Antioxidants (C, E).

31. Describe the effects of physical exercise on the musculoskeletal system.

    • Bones: Increased bone density, improved architecture due to weight-bearing stress.
    • Muscles: Muscle hypertrophy, increased strength, improved endurance (mitochondria, capillaries, glycogen), improved coordination and balance, increased flexibility.
    • Joints: Improved joint health (synovial fluid circulation), stronger ligaments and tendons.

32. Explain the changes in the musculoskeletal system with aging and methods to prevent them.

    • Changes:
      • Bones: Osteoporosis (decreased density, increased fracture risk), Osteoarthritis (cartilage degeneration).
      • Muscles: Sarcopenia (loss of mass, strength), reduced muscle quality.
      • Joints: Decreased flexibility, reduced range of motion.
    • Prevention/Mitigation: Regular weight-bearing and resistance exercise, adequate calcium/Vitamin D/protein intake, fall prevention, hormone therapy (if appropriate), medications.

33. Describe the embryological development of the skeletal system.

    • Develops from mesenchyme.
    • Ossification:
      • Intramembranous Ossification: Direct bone formation from mesenchyme (e.g., skull flat bones).
      • Endochondral Ossification: Bone replaces hyaline cartilage models (most bones).
    • Joint Formation: Mesenchyme between developing bones forms joints.

34. Explain the sexual dimorphism in the human skeletal system.

    • Overall: Male skeletons generally larger, heavier, more robust. Female skeletons lighter, more gracile.
    • Skull: Males: prominent brow ridges, larger mastoid processes, square chin. Females: smoother, smaller features.
    • Pelvis: Female: wider, shallower, larger inlet/outlet, wider subpubic angle (adapted for childbirth). Male: narrower, deeper, heart-shaped, narrower subpubic angle.
    • Long Bones: Males: longer, larger joint surfaces.

35. Describe the adaptation of human skeleton for bipedal locomotion.

    • S-shaped Vertebral Column: Shock absorption, balance.
    • Broad, Bowl-shaped Pelvis: Supports organs, transfers weight to legs, stability.
    • Angled Femur (Valgus Angle): Knees closer to midline for efficient walking.
    • Arched Foot: Shock absorption, propulsion.
    • Non-opposable Big Toe: Stable platform.
    • Foramen Magnum: Centrally located for head balance.
    • Shorter, Broader Scapula: Allows arm swinging.

36. Explain the biomechanics of human movement, including levers and muscle mechanics.

    • Biomechanics: Application of mechanical principles to biological systems.
    • Levers: Musculoskeletal system acts as levers (Fulcrum=joint, Effort=muscle, Load=resistance).
      • Classes: First (fulcrum in middle), Second (load in middle), Third (effort in middle - most common).
    • Muscle Mechanics: Force production (depends on size, fiber type), muscle action (agonists, antagonists, synergists, fixators), length-tension, force-velocity relationships.

37. Describe the role of proprioception and balance in coordinated movement.

    • Proprioception: Sense of body position and movement from receptors in muscles, tendons, joints. Provides feedback to CNS.
    • Balance: Ability to maintain center of gravity over base of support. Involves vestibular, visual, and proprioceptive input.
    • Coordinated Movement: Both are crucial for smooth, efficient, and controlled movements by allowing CNS to adjust muscle activity and maintain posture.

38. Explain the neural control of voluntary movement, including the role of motor cortex.

    • Voluntary Movement: Initiated and controlled by the brain.
    • Motor Cortex: In frontal lobe, plans, initiates, and directs voluntary movements. Contains somatotopic map.
    • Other Brain Areas: Premotor cortex, supplementary motor area (planning), basal ganglia (modulation), cerebellum (coordination, learning).
    • Descending Pathways: Signals travel down spinal cord to motor neurons.
    • Feedback Loops: Sensory feedback allows for adjustments.

39. Describe the reflex mechanisms involved in posture and movement.

    • Reflexes: Involuntary, rapid responses.
    • Stretch Reflex: Muscle stretched -> contracts (e.g., patellar reflex). Maintains posture.
    • Golgi Tendon Reflex: Excessive tension -> muscle relaxes. Protects from damage.
    • Withdrawal Reflex: Painful stimulus -> limb withdrawal.
    • Crossed-Extensor Reflex: Withdrawal in one limb -> extension in opposite limb for balance.
    • Significance: Provide rapid, unconscious adjustments for balance, posture, and protection.

40. Explain the role of the cerebellum in motor coordination and learning.

    • Motor Coordination: Compares intended vs. actual movements, sends corrective signals for smooth, precise, coordinated movements. Responsible for timing.
    • Motor Learning: Adapts and refines motor skills through practice, stores procedural memories, adjusts motor programs.
    • Balance and Posture: Works with vestibular system to maintain equilibrium.

41. Describe the spinal mechanisms controlling locomotion and reflexes.

    • Spinal Cord: Contains neural circuits for rhythmic motor patterns.
    • Central Pattern Generators (CPGs): Spinal circuits that produce rhythmic outputs (e.g., walking) without continuous brain input.
    • Reflexes: Many reflexes (stretch, Golgi tendon, withdrawal) are integrated at spinal level, providing rapid adjustments.
    • Descending Control: Brain modulates CPGs and reflexes for voluntary control and fine-tuning.

42. Explain the development of motor skills from infancy to adulthood.

    • Cephalocaudal & Proximodistal: Head to toe, center outwards.
    • Infancy: Gross motor (head control, rolling, sitting, crawling, walking), fine motor (reaching, grasping).
    • Childhood: Refinement of gross motor (running, jumping), complex fine motor (writing).
    • Adolescence: Further refinement, specialized skills.
    • Adulthood: Maintenance, potential decline if not active.
    • Influences: Genetics, environment, practice, nutrition, neurological maturation.

43. Describe the common injuries of the musculoskeletal system and their prevention.

    • Common Injuries: Fractures (bones), Sprains (ligaments), Strains (muscles/tendons), Dislocations (joints), Tendinitis, Bursitis, Meniscus tears, Rotator cuff tears.
    • Prevention: Warm-up/cool-down, proper technique, gradual progression, strength training, flexibility, proper equipment, nutrition, rest, ergonomics.

44. Explain the principles of rehabilitation after musculoskeletal injuries.

    • Principles: Restore function, reduce pain, prevent re-injury, return to activity.
    • Phases: Acute (RICE, immobilization), Subacute (restore motion), Remodeling/Strengthening (progressive exercise), Return to Activity (functional training).
    • Key Elements: Pain management, range of motion, strengthening, proprioception/balance, functional training, patient education, gradual progression.

45. Describe the use of prosthetics and orthotics in musculoskeletal disorders.

    • Prosthetics: Artificial devices replacing missing body parts (e.g., prosthetic limb). Purpose: restore function, mobility.
    • Orthotics: External devices supporting, aligning, preventing deformity, or improving function (e.g., knee brace). Purpose: support, reduce pain, correct alignment.
    • Role: Used for amputations, cerebral palsy, arthritis, deformities, weaknesses.

46. Explain the role of physical therapy in musculoskeletal health.

    • Physical Therapy: Restores, maintains, maximizes movement and function.
    • Role: Pain management, restoring range of motion, strengthening, improving balance/coordination, gait training, postural correction, patient education, rehabilitation, preventive care.

47. Describe the impact of lifestyle factors on musculoskeletal health.

    • Positive: Regular physical activity (stronger bones/muscles, joint health), balanced nutrition (nutrients for bones/muscles), healthy weight (reduces joint stress).
    • Negative: Sedentary lifestyle (bone/muscle loss, stiffness), poor diet (nutrient deficiency), smoking (reduced bone density, impaired healing), excessive alcohol, poor posture/ergonomics, stress.

48. Explain the genetic disorders affecting the musculoskeletal system.

    • Inherited conditions affecting bone, muscle, or connective tissue.
    • Examples: Muscular Dystrophies (muscle weakness), Osteogenesis Imperfecta (brittle bones), Marfan Syndrome (connective tissue), Achondroplasia (dwarfism), Spinal Muscular Atrophy (motor neurons), Ehlers-Danlos Syndromes (hypermobile joints).

49. Describe the autoimmune conditions affecting muscles and joints.

    • Immune system attacks own tissues.
    • Examples: Rheumatoid Arthritis (joint inflammation), Systemic Lupus Erythematosus (multi-system), Myasthenia Gravis (neuromuscular junction), Polymyositis/Dermatomyositis (muscle inflammation), Ankylosing Spondylitis (spine inflammation), Psoriatic Arthritis.

50. Explain the metabolic disorders affecting bone and muscle health.

    • Disruptions in body's chemical processes.
    • Examples: Osteoporosis (low bone mass), Gout (uric acid in joints), Rickets/Osteomalacia (soft bones from Vitamin D deficiency), Diabetes Mellitus (reduced bone density, muscle weakness), Thyroid Disorders, Kidney Disease.

51. Describe the structure and function of tendons and ligaments in detail.

    • Tendons: Dense regular connective tissue (collagen). Connect muscle to bone. Transmit muscle force for movement.
    • Ligaments: Dense regular connective tissue (collagen, some elastin). Connect bone to bone. Stabilize joints, prevent excessive movement.

52. Explain the healing process of soft tissue injuries in the musculoskeletal system.

    • Phases:
      1. Inflammation (Days 1-6): Bleeding, swelling, immune cell cleanup.
      2. Proliferation/Repair (Days 3-21): Fibroblasts lay collagen, new blood vessels, granulation tissue. Tissue is fragile.
      3. Remodeling/Maturation (Day 21 to 1+ year): Collagen reorganizes, strength increases, scar tissue reabsorbed.

53. Describe the role of inflammation in musculoskeletal disorders and healing.

    • Healing (Acute): Body's protective response, brings immune cells, clears debris, prepares for repair.
    • Disorders (Chronic): Persistent inflammation leads to tissue damage (e.g., in arthritis, tendinitis), pain, loss of function.

54. Explain the pharmacological treatment of musculoskeletal disorders.

    • Pain Relievers: NSAIDs (ibuprofen), acetaminophen, opioids.
    • Anti-inflammatory: Corticosteroids.
    • Disease-Modifying: DMARDs (methotrexate) for autoimmune conditions.
    • Bone-Modifying: Bisphosphonates for osteoporosis.
    • Others: Muscle relaxants, gout medications, calcium/Vitamin D supplements.

55. Describe the surgical interventions for musculoskeletal problems.

    • Fracture Fixation: ORIF (plates, screws), external fixation.
    • Joint Replacement (Arthroplasty): Replacing damaged joints (hip, knee).
    • Arthroscopy: Minimally invasive joint surgery.
    • Ligament/Tendon Repair/Reconstruction.
    • Spinal Surgery: For discs, stenosis, scoliosis.
    • Osteotomy: Bone reshaping.
    • Amputation.

56. Explain the biomechanics of common sports injuries and their prevention.

    • Biomechanics: Study of forces/movements.
    • Injuries: ACL tear (sudden deceleration/cutting), Ankle sprain (inversion), Hamstring strain (high-speed running), Rotator cuff (overhead movements), Patellofemoral pain (muscle imbalance, overuse).
    • Prevention: Proper technique, strength/conditioning, flexibility, warm-up/cool-down, progressive overload, appropriate equipment, rest, nutrition, injury surveillance.

57. Describe the adaptations of the musculoskeletal system to different types of physical training.

    • Resistance Training: Muscle hypertrophy, increased strength, increased bone density, stronger tendons/ligaments.
    • Endurance Training: Increased mitochondrial density, capillary density, oxidative enzymes, myoglobin; minimal hypertrophy.
    • Flexibility Training: Increased range of motion, extensibility of soft tissues.

58. Explain the role of nutrition in athletic performance and muscle development.

    • Energy: Carbohydrates (primary fuel), Fats (long-duration fuel).
    • Muscle Development/Repair: Protein (muscle protein synthesis).
    • Bone Health: Calcium, Vitamin D.
    • Hydration: Water, electrolytes (muscle function, thermoregulation).
    • Micronutrients: B vitamins (energy), antioxidants (C, E).

59. Describe the gender differences in muscle strength and skeletal structure.

    • Muscle Strength: Males generally have greater absolute strength due to higher muscle mass (testosterone). Relative strength differences are smaller.
    • Skeletal Structure: Males: larger, heavier, more robust bones; broader shoulders. Females: lighter, more gracile bones; wider, shallower pelvis (for childbirth).

60. Explain the hormonal influences on muscle and bone development.

    • Growth Hormone (GH) & IGF-1: Promote muscle protein synthesis, bone growth.
    • Testosterone: Potent anabolic (muscle growth, strength), increases bone density.
    • Estrogen: Crucial for bone density (inhibits breakdown), influences muscle.
    • Thyroid Hormones: Influence bone turnover, muscle metabolism.
    • Cortisol: Catabolic (muscle breakdown, bone loss).
    • PTH & Calcitonin: Regulate calcium for bone remodeling.

61. Describe the calcium homeostasis and its regulation in relation to bone health.

    • Calcium Homeostasis: Maintaining stable blood calcium levels.
    • Regulation:
      • PTH (Parathyroid Hormone): Increases blood Ca²⁺ (from bone, kidneys, activates Vit D).
      • Calcitonin: Decreases blood Ca²⁺ (deposits in bone, kidney excretion).
      • Vitamin D (Calcitriol): Increases Ca²⁺ absorption from gut.
    • Bone Health: Ensures adequate calcium for mineralization and remodeling.

62. Explain the vitamin D metabolism and its importance for musculoskeletal health.

    • Metabolism: Skin synthesis (UV), dietary intake, liver conversion to 25(OH)D, kidney conversion to active 1,25(OH)2D (calcitriol).
    • Importance: Essential for calcium absorption, bone mineralization (prevents rickets/osteomalacia), muscle function (prevents weakness).

63. Describe the role of parathyroid hormone in calcium and phosphate regulation.

    • PTH: Released when blood Ca²⁺ is low.
    • Calcium: Increases blood Ca²⁺ by stimulating bone resorption, increasing kidney reabsorption, and activating Vitamin D.
    • Phosphate: Decreases blood phosphate by increasing kidney excretion.

64. Explain the function of calcitonin in bone metabolism.

    • Calcitonin: Released when blood Ca²⁺ is high.
    • Function: Inhibits osteoclast activity (reduces bone breakdown), promotes calcium deposition into bone. Increases kidney calcium excretion. Minor role in adults compared to PTH.

65. Describe the growth hormone effects on musculoskeletal development.

    • Bones: Stimulates longitudinal growth at growth plates, increases bone turnover, maintains bone density.
    • Muscles: Promotes muscle protein synthesis, leading to hypertrophy and increased mass. Increases amino acid uptake.

66. Explain the role of thyroid hormones in bone and muscle metabolism.

    • Bone: Influence bone formation/resorption, crucial for growth plate maturation. Excess can cause bone loss.
    • Muscle: Affect protein turnover, energy production. Excess can cause weakness, deficiency can cause weakness/stiffness.

67. Describe the effects of sex hormones on bone density and muscle mass.

    • Estrogen: Crucial for bone density (inhibits breakdown), contributes to muscle strength. Decline causes osteoporosis.
    • Testosterone: Potent anabolic (muscle growth, strength), increases bone density.
    • Overall: Critical for skeletal maturation, peak bone mass, and maintenance of bone/muscle throughout life.

68. Explain the impact of cortisol on musculoskeletal tissues.

    • Cortisol: Catabolic hormone.
    • Impact: Promotes muscle protein breakdown (weakness, atrophy), inhibits bone formation and stimulates bone resorption (bone loss, osteoporosis risk), can weaken connective tissues.

69. Describe the molecular basis of muscle hypertrophy and atrophy.

    • Hypertrophy (Growth): Net increase in muscle protein synthesis (actin, myosin) over degradation. Involves mTOR pathway, satellite cell activation.
    • Atrophy (Wasting): Protein degradation exceeds synthesis. Involves ubiquitin-proteasome system, autophagy. Caused by disuse, aging, disease.

70. Explain the satellite cells and muscle regeneration.

    • Satellite Cells: Quiescent stem cells in muscle fibers.
    • Regeneration: Activated by injury, proliferate, differentiate into myoblasts, fuse to repair/form new muscle fibers. Some self-renew. Essential for muscle repair and growth.

71. Describe the fiber type composition of different muscles and its functional significance.

    • Slow-Twitch (Type I): High oxidative capacity, slow contraction, fatigue-resistant. For endurance.
    • Fast-Twitch (Type IIa/IIx): High glycolytic capacity, fast contraction, fatigable. For power/sprint.
    • Significance: Proportions vary by muscle function, influencing suitability for endurance vs. power activities.

72. Explain the energy metabolism in different types of muscle fibers.

    • ATP: Direct energy source.
    • Creatine Phosphate System: Rapid ATP for short bursts (Type IIx).
    • Anaerobic Glycolysis: Glucose to lactate for short-medium bursts (Type IIa, IIx).
    • Aerobic Respiration: Efficient ATP from glucose/fats/proteins with oxygen for long duration (Type I, IIa).

73. Describe the lactate production and clearance during exercise.

    • Production: Pyruvate converted to lactate during high-intensity exercise when oxygen is limited.
    • Clearance: Lactate converted back to pyruvate for oxidation (by well-oxygenated muscles, heart, liver) or converted to glucose (Cori cycle in liver).

74. Explain the concept of VO2 max and its relationship to muscle function.

    • VO2 max: Maximum rate of oxygen consumption/utilization during exercise. Indicator of aerobic fitness.
    • Relationship: Reflects oxygen delivery to muscles (cardiovascular efficiency) and muscles' ability to utilize oxygen (mitochondrial density, enzymes, capillaries). Higher VO2 max means better endurance.

75. Describe the cardiovascular adaptations to support muscle function during exercise.

    • Acute: Increased heart rate, stroke volume, cardiac output; blood redistribution to muscles; vasodilation in muscles.
    • Chronic (Training): Cardiac hypertrophy (increased stroke volume), lower resting heart rate, increased blood volume, increased capillary density in muscles.

76. Explain the respiratory adaptations during intense muscular activity.

    • Acute: Increased breathing rate, tidal volume, minute ventilation; increased oxygen extraction; increased diffusion capacity.
    • Chronic (Training): Stronger respiratory muscles, improved lung volumes, more efficient gas exchange.

77. Describe the thermoregulation mechanisms during prolonged muscle activity.

    • Heat Production: Muscle contraction generates heat.
    • Mechanisms: Sweating (evaporation), vasodilation (blood to skin), convection, conduction, radiation.
    • Goal: Dissipate heat to maintain core body temperature.

78. Explain the electrolyte balance and its importance in muscle function.

    • Electrolytes: Charged minerals (Na, K, Ca, Mg).
    • Importance: Critical for nerve impulse transmission, muscle contraction (Ca for initiation, Mg for relaxation), fluid balance, enzyme activity. Imbalances cause cramps, weakness.

79. Describe the hydration requirements for optimal musculoskeletal function.

    • Importance: Water is essential for joint lubrication (synovial fluid), nutrient transport, thermoregulation (sweating), muscle contraction (electrolyte balance), shock absorption (cartilage).
    • Requirements: Varies by activity/climate. Adequate intake before, during, after exercise prevents fatigue, cramps, injury.

80. Explain the role of massage and manual therapy in musculoskeletal health.

    • Role: Pain relief, improved circulation, reduced muscle tension/spasm, increased flexibility/range of motion, reduced swelling, improved tissue healing, stress reduction.
    • Techniques: Effleurage, petrissage, friction, trigger point release, joint mobilization.

81. Describe the biomechanical analysis of human gait and its clinical significance.

    • Gait: Manner of walking. Complex, rhythmic movement.
    • Analysis: Study of forces, movements, muscle activity during walking (motion capture, force plates, EMG).
    • Clinical Significance: Diagnoses abnormal patterns, guides treatment (rehab, orthotics, surgery), monitors progress, identifies injury risk factors, optimizes performance.

82. Explain the postural abnormalities and their impact on musculoskeletal health.

    • Posture: Body position against gravity.
    • Abnormalities: Kyphosis, lordosis, scoliosis, forward head, rounded shoulders.
    • Impact: Chronic pain (back, neck, shoulder), muscle imbalances, joint degeneration (osteoarthritis), reduced mobility, nerve compression, impaired breathing, increased injury risk.

83. Describe the ergonomic principles in preventing musculoskeletal disorders.

    • Ergonomics: Designing workplaces to fit people.
    • Principles: Maintain neutral posture, reduce forceful exertions, minimize repetitive movements, reduce static loads, minimize contact stress, provide adequate lighting, adjustability, work-rest schedules, training.
    • Goal: Reduce physical stress, prevent injuries.

84. Explain the occupational factors affecting musculoskeletal health.

    • Factors: Repetitive tasks, forceful exertions, awkward postures, vibration, contact stress, static loading, cold environments, psychosocial factors.
    • Impact: Overuse injuries, strains, sprains, back pain, nerve compression.
    • Prevention: Ergonomic implementation, job rotation, training.

85. Describe the role of genetics in determining muscle fiber composition.

    • Genetic Predisposition: Influences inherent proportion of slow-twitch (Type I) and fast-twitch (Type II) fibers.
    • Inheritance: Genes affect myosin heavy chain isoforms.
    • Impact: Natural advantage in power/sprint (fast-twitch) or endurance (slow-twitch). Training can induce some shifts, but baseline is genetic.

86. Explain the epigenetic factors influencing musculoskeletal development.

    • Epigenetics: Heritable changes in gene expression without DNA alteration, influenced by environment.
    • Influence: Early life nutrition, physical activity (mechanical loading), stress, aging, disease can epigenetically modify genes related to bone/muscle development, growth, adaptation, and decline.

87. Describe the stem cell therapy applications in musculoskeletal medicine.

    • Stem Cell Therapy: Uses undifferentiated cells to repair/replace damaged tissues.
    • Applications: Cartilage repair (MSCs to chondrocytes), bone regeneration (MSCs to osteoblasts), muscle regeneration (satellite cells), tendon/ligament repair, osteoarthritis treatment.
    • Sources: Bone marrow, adipose tissue, umbilical cord blood.

88. Explain the tissue engineering approaches for musculoskeletal repair.

    • Tissue Engineering: Combines cells, materials, biochemical factors to create biological substitutes.
    • Approaches:
      • Scaffolds: Biodegradable frameworks for cell growth.
      • Cells: Stem cells or differentiated cells seeded on scaffolds.
      • Growth Factors: Guide cell differentiation.
      • Bioreactors: Controlled environment for tissue development.
    • Applications: New cartilage, bone grafts, tendons/ligaments, muscle.

89. Describe the role of growth factors in muscle and bone regeneration.

    • Growth Factors: Proteins stimulating cell proliferation, differentiation, migration.
    • Muscle: IGF-1, FGF, HGF (activate satellite cells, promote hypertrophy).
    • Bone: BMPs (induce bone formation), PDGF, VEGF (angiogenesis), FGF.
    • Clinical: Used to enhance healing in fractures, non-unions, soft tissue injuries.

90. Explain the molecular mechanisms of muscle protein synthesis.

    • MPS: Muscle cells create new proteins from amino acids.
    • Mechanisms:
      • mTOR Pathway: Central regulator, activated by exercise, amino acids, growth factors; promotes translation.
      • Ribosomes: Translate mRNA to protein.
      • Transcription & Translation: DNA to mRNA, mRNA to protein.
      • Amino Acid Availability: Crucial building blocks.
      • Hormonal Influence: Anabolic hormones (testosterone, GH, insulin) stimulate MPS.

91. Describe the autophagy and protein degradation pathways in muscles.

    • Protein Degradation: Breakdown of muscle proteins.
    • Autophagy: Cellular "self-eating" of damaged organelles/proteins for recycling. Contributes to atrophy.
    • Ubiquitin-Proteasome System (UPS): Tags proteins for degradation by proteasome. Major role in muscle atrophy.
    • Balance: MPS vs. degradation determines muscle mass.

92. Explain the mitochondrial function in muscle energy metabolism.

    • Mitochondria: "Powerhouses" for aerobic respiration, producing large ATP.
    • Role: Aerobic ATP production (Krebs cycle, oxidative phosphorylation), fat oxidation, lactate clearance, calcium buffering.
    • Adaptations: Endurance training increases mitochondrial number/size, enhancing aerobic capacity.

93. Describe the oxidative stress and antioxidant mechanisms in muscles.

    • Oxidative Stress: Imbalance of ROS (reactive oxygen species) production and antioxidant defense. ROS damage muscle.
    • Antioxidant Mechanisms:
      • Enzymatic: SOD, Catalase, Glutathione Peroxidase.
      • Non-Enzymatic: Vitamins C, E, Glutathione.
    • Exercise: Acute exercise increases ROS, but regular exercise upregulates defenses.

94. Explain the role of mechanical loading in bone and muscle adaptation.

    • Mechanical Loading: Forces applied to bones/muscles.
    • Bone (Wolff's Law): Increased loading (exercise) stimulates bone formation (increased density). Decreased loading causes bone loss.
    • Muscle: Resistance training (tension) causes hypertrophy. Endurance training (repetitive loading) improves oxidative capacity.
    • Mechanotransduction: Cells sense and respond to mechanical stimuli.

95. Describe the microgravity effects on the musculoskeletal system.

    • Microgravity: Near weightlessness in space, removes normal mechanical loading.
    • Bones: Rapid bone loss (osteopenia/osteoporosis), increased fracture risk, hypercalciuria.
    • Muscles: Rapid muscle atrophy (sarcopenia), loss of strength/endurance, fiber type shifts, reduced neuromuscular control.
    • Mitigation: Exercise, nutrition.

96. Explain the comparative anatomy of locomotion in different vertebrates.

    • Fish: Streamlined, fins, undulatory movement.
    • Amphibians: Splayed limbs, sprawling gait.
    • Reptiles: More upright, some sprawling.
    • Birds: Adapted for flight (hollow bones, powerful pectorals, keeled sternum).
    • Mammals: Diverse (quadrupeds, bipeds, arboreal, aquatic) with specialized limb adaptations.

97. Describe the evolutionary adaptations of the human musculoskeletal system.

    • Bipedalism: S-shaped spine, broad pelvis, angled femur, arched foot, non-opposable big toe, central foramen magnum.
    • Upper Limb: Dexterous hand (opposable thumb), mobile shoulder.
    • Brain/Skull: Larger cranium.
    • Overall: Efficient locomotion, freed hands for tool use, manipulation.

98. Explain the biomimetic applications inspired by animal locomotion.

    • Biomimetics: Imitation of nature to solve human problems.
    • Applications:
      • Robotics: Legged (mammals, insects), swimming (fish), flying (birds, insects).
      • Vehicle Design: Aerodynamics (birds, fish).
      • Prosthetics/Orthotics: Mimicking natural limb biomechanics.
      • Medical Devices: Flexible robots (snake movement).
      • Materials Science: Bone/cartilage properties.

99. Describe the future directions in musculoskeletal research and therapy.

    • Regenerative Medicine: Advanced stem cell therapies, complex tissue engineering, gene therapy.
    • Personalized Medicine: Tailored treatments.
    • Advanced Imaging: High-resolution visualization.
    • Biomaterials: Smart, biocompatible materials.
    • Robotics & AI: Exoskeletons, AI for diagnosis/treatment.
    • Prevention: Deeper understanding of risk factors.
    • Pharmacology: Novel drugs targeting molecular pathways.

100. Explain the integration of technology in musculoskeletal assessment and treatment.

• Assessment: Advanced imaging (MRI, CT), wearable sensors (gait, posture), motion capture, EMG, force plates.
• Treatment: Rehabilitation robotics, surgical robotics, exoskeletons, telemedicine, VR/AR for rehab, 3D printing (prosthetics), biofeedback, smart implants.
• Overall: Technology enhances precision, objectivity, personalization, and accessibility in care.