Respiratory System Question Paper

Section A: Multiple Choice Questions (MCQs) - 100 Questions (1 mark each)

Instructions: Choose the correct answer from the given options.

The primary function of the respiratory system is: a) Digestion of food b) Exchange of gases c) Blood circulation d) Waste excretion
Which organ filters, warms, and moistens inhaled air? a) Larynx b) Trachea c) Nose d) Pharynx
The voice box is also known as: a) Pharynx b) Larynx c) Trachea d) Bronchi
The windpipe is scientifically called: a) Bronchi b) Larynx c) Pharynx d) Trachea
Gas exchange in the lungs occurs in: a) Bronchi b) Trachea c) Alveoli d) Larynx
The trachea is supported by: a) Flat bones b) C-shaped cartilaginous rings c) Muscles only d) Ligaments
Which structure contains vocal cords? a) Pharynx b) Trachea c) Larynx d) Bronchi
The pharynx is a common passageway for: a) Air only b) Food only c) Both air and food d) Blood only
The main bronchi divide into smaller: a) Alveoli b) Bronchioles c) Trachea d) Pharynx
Respiration is a: a) Physical process b) Biochemical process c) Mechanical process d) Chemical process only
Breathing is a: a) Biochemical process b) Physical process c) Cellular process d) Enzymatic process
Energy is released from food during: a) Breathing b) Respiration c) Inhalation d) Exhalation
Respiration occurs in: a) Lungs only b) Nose c) Cells (mitochondria) d) Trachea
Which process involves many enzymes? a) Breathing b) Respiration c) Inhalation d) Exhalation
During inhalation, the diaphragm: a) Relaxes and moves upward b) Contracts and moves downward c) Remains stationary d) Moves sideways
During exhalation, the ribs move: a) Upward and outward b) Downward and inward c) Sideways only d) Remain stationary
Intercostal muscles are associated with: a) Diaphragm b) Ribs c) Lungs d) Heart
When chest cavity volume increases, lung pressure: a) Increases b) Decreases c) Remains same d) Fluctuates
Air rushes into lungs when pressure inside is: a) Higher than outside b) Lower than outside c) Equal to outside d) Very high
Asthma is characterized by: a) Bacterial infection b) Chronic inflammation of airways c) Fluid in lungs d) Broken ribs
Bronchitis affects: a) Alveoli b) Trachea c) Bronchial tubes d) Nose
Pneumonia causes inflammation of: a) Bronchi b) Trachea c) Air sacs d) Pharynx
Tuberculosis is caused by: a) Virus b) Bacteria c) Fungus d) Allergy
Which disease mainly affects the lungs but can affect other body parts? a) Asthma b) Bronchitis c) Pneumonia d) Tuberculosis
Wheezing is a symptom of: a) Tuberculosis b) Asthma c) Heart disease d) Kidney disease
The nose contains receptors for: a) Taste b) Touch c) Smell d) Sound
How many main bronchi are there? a) One b) Two c) Three d) Four
The chest cavity is also called: a) Abdominal cavity b) Thoracic cavity c) Pelvic cavity d) Cranial cavity
During normal breathing, which muscle is most important? a) Heart muscle b) Diaphragm c) Arm muscle d) Leg muscle
Coughing with mucus is a symptom of: a) Asthma only b) Bronchitis c) Heart attack d) Kidney stones
The abbreviation T.B. stands for: a) Total Breathing b) Tuberculosis c) Throat Blockage d) Tiny Bacteria
Pneumonia may fill air sacs with: a) Air only b) Blood only c) Fluid or pus d) Mucus only
Which is NOT a function of the nose? a) Filtering air b) Warming air c) Producing sound d) Moistening air
The larynx connects to: a) Esophagus b) Trachea c) Stomach d) Heart
Difficulty breathing is called: a) Dyspnea b) Tachycardia c) Hypertension d) Diabetes
Which gas is taken in during breathing? a) Carbon dioxide b) Oxygen c) Nitrogen d) Hydrogen
Which gas is expelled during breathing? a) Oxygen b) Carbon dioxide c) Nitrogen d) Helium
The windpipe divides into: a) Alveoli b) Bronchi c) Pharynx d) Larynx
Chronic means: a) Temporary b) Long-lasting c) Painful d) Infectious
Air sacs in lungs are called: a) Bronchi b) Bronchioles c) Alveoli d) Trachea
The process of taking air in is called: a) Exhalation b) Inhalation c) Respiration d) Circulation
The process of giving air out is called: a) Inhalation b) Exhalation c) Respiration d) Digestion
Which structure prevents the trachea from collapsing? a) Muscles b) Bones c) Cartilaginous rings d) Ligaments
Inflammation of airways is seen in: a) Heart disease b) Asthma c) Kidney stones d) Broken bones
Fever and chills are symptoms of: a) Asthma b) Simple cold c) Pneumonia d) Healthy breathing
The respiratory system works with which other system for gas transport? a) Digestive system b) Circulatory system c) Nervous system d) Skeletal system
During exercise, breathing rate: a) Decreases b) Increases c) Stops d) Remains same
Which is the correct breathing pathway? a) Nose → Larynx → Pharynx → Trachea b) Nose → Pharynx → Larynx → Trachea c) Nose → Trachea → Pharynx → Larynx d) Larynx → Nose → Pharynx → Trachea
Chest tightness is a symptom of: a) Good health b) Asthma c) Strong muscles d) Proper diet
The primary organs of respiration are: a) Heart and liver b) Kidneys c) Lungs d) Brain and spinal cord
Intercostal muscles are located between: a) Bones of arms b) Ribs c) Leg bones d) Skull bones
When diaphragm relaxes, it moves: a) Downward b) Upward c) Sideways d) In circles
Bacterial infection of lungs may cause: a) Asthma b) Pneumonia c) Heart attack d) Broken ribs
Which disease is infectious? a) Asthma b) Tuberculosis c) Broken bones d) Heart attack
Olfactory receptors are found in: a) Eyes b) Ears c) Nose d) Mouth
The trachea is approximately how long in adults? a) 2-3 cm b) 10-12 cm c) 20-25 cm d) 50 cm
How many alveoli are approximately in human lungs? a) Thousands b) Millions c) Hundreds of millions d) Billions
Which muscle contracts during inhalation? a) Heart muscle b) Diaphragm c) Stomach muscle d) Brain muscle
The voice is produced by vibration of: a) Trachea b) Bronchi c) Vocal cords d) Alveoli
Mucus production increases in: a) Healthy lungs b) Bronchitis c) Strong breathing d) Exercise
Air enters the body through: a) Mouth only b) Nose only c) Both nose and mouth d) Ears
The epiglottis prevents food from entering: a) Stomach b) Esophagus c) Trachea d) Mouth
Smoking primarily affects: a) Heart only b) Respiratory system c) Kidneys only d) Bones only
Oxygen is carried in blood by: a) White blood cells b) Platelets c) Red blood cells d) Plasma only
Carbon dioxide is a: a) Useful gas for body b) Waste product c) Essential nutrient d) Vitamin
Hiccups involve spasms of: a) Heart b) Diaphragm c) Liver d) Kidneys
The right lung has how many lobes? a) One b) Two c) Three d) Four
The left lung has how many lobes? a) One b) Two c) Three d) Four
Respiratory rate is usually measured in: a) Breaths per second b) Breaths per minute c) Breaths per hour d) Breaths per day
Normal respiratory rate for adults is approximately: a) 5-8 breaths per minute b) 12-20 breaths per minute c) 30-40 breaths per minute d) 50-60 breaths per minute
Which is NOT a respiratory disease mentioned? a) Asthma b) Bronchitis c) Diabetes d) Pneumonia
Cellular respiration produces: a) Oxygen b) Carbon dioxide c) Nitrogen d) Hydrogen
The pleura is: a) A lung disease b) Membrane covering lungs c) Part of heart d) Breathing muscle
Expiration is another term for: a) Inhalation b) Exhalation c) Respiration d) Circulation
Inspiration is another term for: a) Exhalation b) Inhalation c) Circulation d) Digestion
The medulla oblongata controls: a) Heartbeat only b) Breathing rhythm c) Digestion only d) Vision only
High altitude affects breathing because of: a) More oxygen b) Less oxygen c) More carbon dioxide d) Cold temperature only
Artificial respiration is given when: a) Person is healthy b) Person stops breathing c) Person is sleeping d) Person is eating
Spirometer measures: a) Heart rate b) Blood pressure c) Lung capacity d) Body temperature
Vital capacity refers to: a) Heart pumping ability b) Maximum air lungs can hold c) Kidney function d) Brain activity
Residual volume is: a) Air always in lungs b) Air breathed out c) Air breathed in d) Total lung capacity
Tidal volume is: a) Air in normal breathing b) Maximum air capacity c) Air left in lungs d) Air in deep breathing
Which gas makes up most of atmospheric air? a) Oxygen b) Carbon dioxide c) Nitrogen d) Hydrogen
Oxygen percentage in atmospheric air is approximately: a) 78% b) 21% c) 1% d) 50%
Carbon dioxide percentage in atmospheric air is approximately: a) 21% b) 78% c) 0.03% d) 10%
Hyperventilation means: a) Normal breathing b) Fast, deep breathing c) Slow breathing d) No breathing
Hypoventilation means: a) Fast breathing b) Slow, shallow breathing c) Normal breathing d) Deep breathing
Apnea means: a) Fast breathing b) Slow breathing c) Temporary stopping of breathing d) Deep breathing
The Adam's apple is part of: a) Throat b) Larynx c) Trachea d) Esophagus
Cilia in respiratory tract help in: a) Gas exchange b) Filtering and cleaning air c) Sound production d) Smell detection
Surfactant in alveoli helps in: a) Gas exchange b) Preventing collapse c) Sound production d) Mucus production
Which cells produce surfactant? a) Red blood cells b) White blood cells c) Pneumocytes d) Nerve cells
Emphysema affects: a) Heart b) Alveoli c) Kidneys d) Brain
Chronic obstructive pulmonary disease (COPD) includes: a) Heart diseases b) Emphysema and chronic bronchitis c) Kidney diseases d) Brain disorders
Pulmonary edema involves: a) Dry lungs b) Fluid accumulation in lungs c) No air in lungs d) Extra air in lungs
Which hormone can affect breathing rate? a) Insulin b) Adrenaline c) Growth hormone d) Thyroid hormone
The phrenic nerve controls: a) Heart b) Diaphragm c) Liver d) Kidneys
Cheyne-Stokes breathing is: a) Normal breathing b) Abnormal breathing pattern c) Fast breathing d) Slow breathing
Peak flow meter measures: a) Heart rate b) Maximum speed of exhaled air c) Blood pressure d) Body temperature
Respiratory quotient (RQ) is the ratio of: a) O₂ consumed to CO₂ produced b) CO₂ produced to O₂ consumed c) Heart rate to breathing rate d) Lung capacity to body weight

Section B: Short Answer Questions (1 mark each) - 100 Questions

Instructions: Write brief answers in one or two sentences.

Name the primary function of the respiratory system.
List three functions of the nose in respiration.
What is the scientific name for the windpipe?
Where are the vocal cords located?
What are alveoli?
Define respiration.
Define breathing.
What is the diaphragm?
Name two gases involved in respiration.
What is asthma?
What causes bronchitis?
Define pneumonia.
What is tuberculosis?
What happens to the diaphragm during inhalation?
What happens to the ribs during exhalation?
Name the muscle between the ribs.
What is the pharynx?
What supports the trachea?
What are bronchioles?
Where does cellular respiration occur?
What is the larynx commonly called?
What is another name for breathing in?
What is another name for breathing out?
What is the chest cavity also known as?
Name one symptom of asthma.
What type of infection is tuberculosis?
What fills the air sacs in pneumonia?
What is chronic inflammation?
Define tidal volume.
What is vital capacity?
What is residual volume?
Name the membrane covering the lungs.
What controls breathing rhythm in the brain?
What is artificial respiration?
What does a spirometer measure?
What is hyperventilation?
What is apnea?
What is the Adam's apple?
What are cilia?
What is surfactant?
Name the nerve that controls the diaphragm.
What is emphysema?
What does COPD stand for?
What is pulmonary edema?
What is a peak flow meter used for?
Define respiratory quotient.
What percentage of air is oxygen?
What percentage of air is nitrogen?
What is the epiglottis?
How many lobes does the right lung have?
How many lobes does the left lung have?
What is the normal respiratory rate for adults?
What carries oxygen in blood?
What is carbon dioxide in relation to the body?
What causes hiccups?
What is inspiration?
What is expiration?
What affects breathing at high altitudes?
What is hypoventilation?
What type of process is breathing?
What type of process is respiration?
Where do bronchi lead to?
What connects the nasal cavity to the larynx?
What prevents the trachea from collapsing?
What is the main function of alveoli?
Name one function of intercostal muscles.
What happens to chest cavity volume during inhalation?
What happens to lung pressure when chest cavity expands?
When does air rush into the lungs?
What is wheezing?
What produces mucus in bronchitis?
Name one symptom of pneumonia.
Which body system does tuberculosis mainly affect?
What is chest tightness?
Name the receptors found in the nose.
What divides into two main bronchi?
What are the primary organs of respiration?
Where are intercostal muscles located?
What happens when diaphragm relaxes?
What type of infection can cause pneumonia?
Is tuberculosis infectious?
Where are olfactory receptors found?
What produces voice?
What increases in bronchitis?
How does air enter the body?
What does the epiglottis prevent?
What does smoking primarily affect?
What carries carbon dioxide in blood?
What are spasms of diaphragm called?
How is respiratory rate measured?
What is cellular respiration's main product?
What is another term for exhalation?
What is another term for inhalation?
What part of brain controls breathing?
Why is breathing difficult at high altitude?
When is artificial respiration needed?
What is lung capacity?
What is always present in lungs?
What is normal breathing volume called?
What makes up most of atmospheric air?

Section C: Short Answer Questions (2 marks each) - 25 Questions

Instructions: Provide detailed answers explaining the concepts clearly.

Explain the difference between respiration and breathing with two points each.
Describe the mechanism of inhalation including the role of diaphragm and ribs.
Explain the mechanism of exhalation and how it differs from inhalation.
List the main parts of the respiratory system and state one function of each.
Compare the location and enzyme involvement between respiration and breathing.
Describe three main symptoms of asthma and explain why they occur.
Explain bronchitis: what it is, what causes it, and its main symptoms.
Describe pneumonia including what happens to the air sacs and common symptoms.
Explain tuberculosis as a disease, mentioning its cause and primary affected organ.
Describe the pathway of air from nose to lungs, naming all structures involved.
Explain the role of cartilaginous rings in the trachea and why they are C-shaped.
Describe the structure and function of alveoli in gas exchange.
Explain how the pharynx functions as a common passageway and what it connects.
Describe the larynx, its location, and its two main functions.
Explain the relationship between chest cavity volume and lung pressure during breathing.
Compare the energy aspects of respiration and breathing processes.
Describe the role of intercostal muscles in the breathing mechanism.
Explain why the nose is important in respiratory function with three specific reasons.
Describe how bronchi and bronchioles are related and their functions.
Explain the difference between chronic and acute respiratory conditions with examples.
Describe what happens during gas exchange in the lungs and where it occurs.
Explain the importance of the respiratory system working with the circulatory system.
Describe three ways the respiratory system protects itself from harmful substances.
Explain how breathing rate changes during exercise and why this happens.
Describe the consequences of respiratory diseases on normal breathing function.

Section D: Long Answer Questions (3 marks each) - 25 Questions

Instructions: Provide comprehensive answers with detailed explanations, examples, and reasoning.

Draw a labeled diagram of the respiratory system and explain the function of each labeled part in detail.
Explain the complete mechanism of breathing including both inhalation and exhalation phases. Describe the role of muscles, pressure changes, and air movement.
Compare and contrast respiration and breathing in detail. Include differences in process type, location, energy involvement, and enzymes. Provide examples to support your explanation.
Describe four major respiratory diseases mentioned in the text. For each disease, explain the cause, main symptoms, affected parts, and distinguishing features.
Explain the pathway of air from the external environment to the site of gas exchange. Describe what happens to the air at each stage and the importance of each structure.
Analyze the importance of the diaphragm in breathing. Explain its structure, location, nerve supply, and detailed mechanism of action during both phases of breathing.
Discuss the role of pressure differences in breathing mechanism. Explain how pressure changes occur, why air moves, and what happens when this mechanism is disrupted.
Explain the protective mechanisms of the respiratory system. Describe how the nose, trachea, and other structures protect the lungs from harmful substances and pathogens.
Analyze the relationship between the respiratory and circulatory systems. Explain how they work together for gas transport and what happens when either system fails.
Describe the structure and function of alveoli in detail. Explain their design features that make them efficient for gas exchange and what can go wrong with them.
Explain asthma as a chronic respiratory condition. Describe its pathophysiology, triggers, symptoms, and how it affects normal breathing mechanism.
Discuss tuberculosis as an infectious respiratory disease. Explain its causative agent, transmission, symptoms, affected organs, and why it's considered serious.
Analyze pneumonia and its effects on respiratory function. Explain different types, causes, how it affects gas exchange, and its symptoms.
Explain the concept of lung volumes and capacities. Describe tidal volume, vital capacity, and residual volume with their significance in respiratory health.
Discuss the neural control of breathing. Explain which parts of the brain are involved, how breathing rhythm is maintained, and what can affect this control.
Analyze the effects of environmental factors on respiratory health. Discuss pollution, altitude, temperature, and humidity effects on breathing and lung function.
Explain the emergency responses of the respiratory system. Describe what happens during breath-holding, choking, and how artificial respiration works.
Discuss the age-related changes in respiratory function. Explain how breathing mechanism and lung capacity change with age and their implications.
Analyze the role of respiratory system in maintaining body pH. Explain how breathing rate changes affect acid-base balance and body homeostasis.
Explain respiratory adaptations during physical exercise. Describe immediate and long-term changes in breathing pattern, lung function, and oxygen utilization.
Discuss smoking effects on the respiratory system. Explain how tobacco affects different parts of respiratory system and leads to various diseases.
Analyze sleep-related breathing disorders. Explain sleep apnea, its causes, effects on health, and relationship with normal breathing mechanism.
Explain respiratory first aid measures. Describe techniques for helping someone with breathing difficulties, when to use them, and their scientific basis.
Discuss occupational respiratory diseases. Explain how work environment can affect lung health, give examples, and describe prevention measures.
Analyze the future of respiratory health. Discuss emerging respiratory diseases, treatment advances, and preventive measures for maintaining healthy respiratory function.

Answer Key Instructions

Respiratory System Answer Script

Section A: Multiple Choice Questions (MCQs)

b) Exchange of gases
c) Nose
b) Larynx
d) Trachea
c) Alveoli
b) C-shaped cartilaginous rings
c) Larynx
c) Both air and food
b) Bronchioles
b) Biochemical process
b) Physical process
b) Respiration
c) Cells (mitochondria)
b) Respiration
b) Contracts and moves downward
b) Downward and inward
b) Ribs
b) Decreases
b) Lower than outside
b) Chronic inflammation of airways
c) Bronchial tubes
c) Air sacs
b) Bacteria
d) Tuberculosis
b) Asthma
c) Smell
b) Two
b) Thoracic cavity
b) Diaphragm
b) Bronchitis
b) Tuberculosis
c) Fluid or pus
c) Producing sound
b) Trachea
a) Dyspnea
b) Oxygen
b) Carbon dioxide
b) Bronchi
b) Long-lasting
c) Alveoli
b) Inhalation
b) Exhalation
c) Cartilaginous rings
b) Asthma
c) Pneumonia
b) Circulatory system
b) Increases
b) Nose → Pharynx → Larynx → Trachea
b) Asthma
c) Lungs
b) Ribs
b) Upward
b) Pneumonia
b) Tuberculosis
c) Nose
b) 10-12 cm
c) Hundreds of millions
b) Diaphragm
c) Vocal cords
b) Bronchitis
c) Both nose and mouth
c) Trachea
b) Respiratory system
c) Red blood cells
b) Waste product
b) Diaphragm
c) Three
b) Two
b) Breaths per minute
b) 12-20 breaths per minute
c) Diabetes
b) Carbon dioxide
b) Membrane covering lungs
b) Exhalation
b) Inhalation
b) Breathing rhythm
b) Less oxygen
b) Person stops breathing
c) Lung capacity
b) Maximum air lungs can hold
a) Air always in lungs
a) Air in normal breathing
c) Nitrogen
b) 21%
c) 0.03%
b) Fast, deep breathing
b) Slow, shallow breathing
c) Temporary stopping of breathing
b) Larynx
b) Filtering and cleaning air
b) Preventing collapse
c) Pneumocytes
b) Alveoli
b) Emphysema and chronic bronchitis
b) Fluid accumulation in lungs
b) Adrenaline
b) Diaphragm
b) Abnormal breathing pattern
b) Maximum speed of exhaled air
b) CO₂ produced to O₂ consumed

Section B: Short Answer Questions (1 mark each)

Primary function: Gas exchange (oxygen in, carbon dioxide out).
Nose functions: Filters, warms, and moistens inhaled air.
Windpipe scientific name: Trachea.
Vocal cords location: Larynx.
Alveoli: Tiny air sacs in the lungs where gas exchange occurs.
Respiration: The biochemical process in cells that releases energy from food.
Breathing: The physical process of inhaling and exhaling air.
Diaphragm: A large muscle at the base of the chest cavity that controls breathing.
Gases in respiration: Oxygen and Carbon Dioxide.
Asthma: A chronic inflammatory disease of the airways causing breathing difficulty.
Bronchitis cause: Inflammation of the bronchial tubes, often due to infection or irritants.
Pneumonia: An infection that inflames the air sacs in the lungs, which may fill with fluid.
Tuberculosis: A serious infectious bacterial disease that mainly affects the lungs.
Diaphragm during inhalation: It contracts and moves downward.
Ribs during exhalation: They move downward and inward.
Muscle between ribs: Intercostal muscles.
Pharynx: A common passageway for both air and food.
Trachea support: C-shaped cartilaginous rings.
Bronchioles: Smaller branches of the bronchi that lead to the alveoli.
Cellular respiration location: Mitochondria within cells.
Larynx common name: Voice box.
Breathing in another name: Inhalation or inspiration.
Breathing out another name: Exhalation or expiration.
Chest cavity other name: Thoracic cavity.
Asthma symptom: Wheezing, coughing, or chest tightness.
Tuberculosis infection type: Bacterial.
Pneumonia air sac filling: Fluid or pus.
Chronic inflammation: Long-lasting inflammation.
Tidal volume: The amount of air inhaled or exhaled during normal breathing.
Vital capacity: The maximum amount of air a person can exhale after a maximum inhalation.
Residual volume: The amount of air remaining in the lungs after a maximal exhalation.
Lung covering membrane: Pleura.
Breathing rhythm control: Medulla oblongata in the brainstem.
Artificial respiration: The process of manually assisting someone to breathe.
Spirometer measures: Lung capacity and volumes.
Hyperventilation: Abnormally fast and deep breathing.
Apnea: Temporary cessation of breathing.
Adam's apple: The protrusion of the thyroid cartilage of the larynx.
Cilia: Tiny hair-like structures that filter and move mucus in the airways.
Surfactant: A substance in the alveoli that prevents them from collapsing.
Diaphragm nerve: Phrenic nerve.
Emphysema: A lung condition that causes shortness of breath due to damaged alveoli.
COPD stands for: Chronic Obstructive Pulmonary Disease.
Pulmonary edema: Excess fluid in the lungs.
Peak flow meter use: Measures the maximum speed of exhalation, used to monitor asthma.
Respiratory quotient: The ratio of CO2 produced to O2 consumed during metabolism.
Oxygen percentage in air: Approximately 21%.
Nitrogen percentage in air: Approximately 78%.
Epiglottis: A flap of cartilage that covers the trachea during swallowing.
Right lung lobes: Three.
Left lung lobes: Two.
Normal adult respiratory rate: 12-20 breaths per minute.
Oxygen carrier in blood: Hemoglobin in red blood cells.
Carbon dioxide relation to body: A waste product of metabolism.
Hiccups cause: Spasms of the diaphragm.
Inspiration: The act of breathing in.
Expiration: The act of breathing out.
High altitude breathing effect: Lower oxygen availability.
Hypoventilation: Abnormally slow and shallow breathing.
Breathing process type: Physical/mechanical process.
Respiration process type: Biochemical process.
Bronchi lead to: The lungs, branching into bronchioles.
Nasal cavity to larynx connection: The pharynx.
Trachea collapse prevention: C-shaped cartilaginous rings.
Alveoli main function: Gas exchange.
Intercostal muscle function: Elevate and depress the ribs during breathing.
Chest cavity volume during inhalation: It increases.
Lung pressure when chest expands: It decreases.
When air rushes into lungs: When lung pressure is lower than atmospheric pressure.
Wheezing: A high-pitched whistling sound made while breathing, often associated with asthma.
Mucus production in bronchitis: Inflamed bronchial tubes.
Pneumonia symptom: Cough, fever, chills, or difficulty breathing.
Tuberculosis main affected system: Respiratory system (lungs).
Chest tightness: A sensation of pressure or squeezing in the chest.
Nose receptors: Olfactory receptors for smell.
Divides into two main bronchi: The trachea.
Primary organs of respiration: The lungs.
Intercostal muscles location: Between the ribs.
Diaphragm relaxation: It moves upward.
Pneumonia infection type: Can be bacterial, viral, or fungal.
Is tuberculosis infectious? Yes.
Olfactory receptors location: In the nasal cavity.
Voice production: Vibration of the vocal cords in the larynx.
Increases in bronchitis: Mucus production.
How air enters body: Through the nose and mouth.
Epiglottis prevention: Prevents food from entering the trachea.
Smoking's primary effect: Affects the respiratory system.
Carbon dioxide carrier in blood: Primarily as bicarbonate ions in plasma, and also bound to hemoglobin.
Diaphragm spasms: Hiccups.
Respiratory rate measurement: Breaths per minute.
Cellular respiration main product: ATP (energy), with CO2 and water as byproducts.
Exhalation other term: Expiration.
Inhalation other term: Inspiration.
Brain part controlling breathing: Medulla oblongata.
High altitude breathing difficulty: Lower partial pressure of oxygen.
Artificial respiration need: When a person stops breathing.
Lung capacity: The total amount of air the lungs can hold.
Always present in lungs: Residual volume of air.
Normal breathing volume name: Tidal volume.
Makes up most of atmospheric air: Nitrogen.

Section C: Short Answer Questions (2 marks each)

Respiration vs. Breathing: Breathing is a physical process of inhaling and exhaling air, involving the lungs and muscles. Respiration is a biochemical process occurring inside cells (mitochondria) to release energy from food, involving enzymes.
Mechanism of Inhalation: During inhalation, the diaphragm contracts and moves down, while the intercostal muscles contract, pulling the ribs up and out. This increases the volume of the thoracic cavity, which lowers the pressure inside the lungs, causing air to rush in.
Mechanism of Exhalation: Exhalation is typically a passive process. The diaphragm and intercostal muscles relax, causing the ribs to move down and in and the diaphragm to move up. This decreases the thoracic cavity volume, increasing lung pressure and forcing air out.
Main Respiratory Parts & Functions:
- Nose: Filters, warms, and moistens air.
- Pharynx: Passageway for air and food.
- Larynx: Produces sound (voice).
- Trachea: Carries air to the bronchi.
- Lungs: Site of gas exchange.
Location & Enzymes (Respiration vs. Breathing): Breathing occurs in the lungs and respiratory passages and involves no enzymes. Cellular respiration occurs inside the mitochondria of all body cells and requires numerous enzymes to proceed.
Asthma Symptoms: Asthma causes wheezing, a whistling sound from narrowed airways; coughing, an attempt to clear the airways; and chest tightness, a feeling of pressure. These occur because inflammation and muscle constriction narrow the airways, making it hard to breathe.
Bronchitis: Bronchitis is the inflammation of the lining of the bronchial tubes. It is often caused by viral or bacterial infections. Its main symptom is a persistent cough that produces mucus.
Pneumonia: Pneumonia is an infection that inflames the alveoli (air sacs) in the lungs. The air sacs may fill with fluid or pus, which interferes with gas exchange. Common symptoms include cough, fever, chills, and difficulty breathing.
Tuberculosis (TB): TB is a serious infectious disease caused by the bacterium Mycobacterium tuberculosis. It primarily affects the lungs but can spread to other parts of the body. It is transmitted through the air when an infected person coughs or sneezes.
Air Pathway: Air enters through the Nose/Mouth → Pharynx → Larynx → Trachea → Bronchi → Bronchioles → Alveoli in the lungs.
Tracheal Rings: The C-shaped cartilaginous rings provide support to the trachea, preventing it from collapsing and ensuring the airway remains open. They are C-shaped to allow the esophagus, which runs behind the trachea, to expand when swallowing food.
Alveoli Structure & Function: Alveoli are tiny, thin-walled air sacs clustered at the end of bronchioles. Their thin walls, large surface area, and rich blood supply from surrounding capillaries make them perfectly suited for the efficient exchange of oxygen and carbon dioxide between the lungs and the blood.
Pharynx Function: The pharynx, or throat, serves as a common passageway for both air traveling to the larynx and food traveling to the esophagus. It connects the nasal and oral cavities to the larynx and esophagus, directing traffic for both the respiratory and digestive systems.
Larynx Description: The larynx, or voice box, is located in the neck between the pharynx and the trachea. Its two main functions are to produce sound via the vibration of the vocal cords and to prevent food from entering the trachea during swallowing via the epiglottis.
Chest Volume & Lung Pressure: During breathing, there is an inverse relationship between chest cavity volume and lung pressure. When the chest volume increases (inhalation), the pressure inside the lungs decreases, drawing air in. When the chest volume decreases (exhalation), the pressure inside the lungs increases, forcing air out.
Energy in Respiration vs. Breathing: Breathing is a mechanical process that consumes a small amount of energy to power muscle contractions. Respiration is a biochemical process that releases a large amount of energy from the chemical bonds in food molecules (like glucose) for the body to use.
Intercostal Muscles Role: The intercostal muscles, located between the ribs, play a key role in breathing. The external intercostals contract to lift the rib cage up and out during inhalation, increasing chest volume. The internal intercostals can contract during forced exhalation to pull the rib cage down and in.
Nose Importance: The nose is important because it filters out dust and particles with its hairs and mucus, warms the inhaled air to body temperature, and moistens the air to prevent the delicate lung tissue from drying out.
Bronchi and Bronchioles: The trachea divides into two main bronchi, one for each lung. Inside the lungs, these bronchi branch repeatedly into smaller and smaller tubes called bronchioles. Both structures serve as conduits to carry air deeper into the lungs, terminating at the alveoli.
Chronic vs. Acute Respiratory Conditions: Acute conditions, like the common cold or acute bronchitis, are sudden and short-term. Chronic conditions, like asthma or COPD, are long-lasting and often progressive, requiring ongoing management.
Gas Exchange: Gas exchange occurs in the alveoli of the lungs. Oxygen from the inhaled air diffuses across the thin walls of the alveoli and into the surrounding capillaries to enter the bloodstream. Simultaneously, carbon dioxide, a waste product from the body, diffuses from the blood into the alveoli to be exhaled.
Respiratory & Circulatory System Importance: These two systems are critically linked. The respiratory system is responsible for taking in oxygen and removing carbon dioxide from the body. The circulatory system is responsible for transporting these gases between the lungs and the body's cells. Without one, the other cannot function to sustain life.
Respiratory Protective Mechanisms: The respiratory system is protected by: 1) Nasal hairs and mucus that trap particles. 2) Cilia in the trachea and bronchi that sweep mucus and debris upward to be coughed out. 3) Coughing and sneezing reflexes that forcefully expel irritants.
Breathing During Exercise: During exercise, the breathing rate and depth increase significantly. This happens because the working muscles produce more carbon dioxide and consume more oxygen. The brain detects these changes in the blood and signals the respiratory muscles to work harder to supply the needed oxygen and remove the excess CO2.
Consequences of Respiratory Diseases: Respiratory diseases disrupt normal breathing by various mechanisms. For example, asthma narrows the airways, making it difficult to move air. Pneumonia fills the alveoli with fluid, impairing gas exchange. These disruptions lead to symptoms like shortness of breath, low blood oxygen levels, and reduced physical capacity.

Section D: Long Answer Questions (3 marks each)

Respiratory System Diagram & Functions: (A diagram would be drawn here).
- Nose: Filters, warms, and moistens incoming air.
- Pharynx: A shared passage for air and food.
- Larynx: The voice box, contains vocal cords for sound production.
- Trachea: The windpipe, a tube reinforced with cartilage that carries air to the lungs.
- Bronchi: Two main branches off the trachea, leading into each lung.
- Lungs: The primary organs where gas exchange occurs.
- Diaphragm: A large muscle beneath the lungs that drives the act of breathing.
Complete Mechanism of Breathing: Breathing involves two phases. Inhalation is an active process where the diaphragm contracts and flattens, and the external intercostal muscles contract, lifting the rib cage up and out. This combined action increases the volume of the thoracic cavity, causing the pressure within the lungs to drop below atmospheric pressure, and air rushes in. Exhalation is usually passive. The diaphragm and intercostal muscles relax, the chest cavity recoils to its smaller resting size, which increases the pressure in the lungs above atmospheric pressure, forcing air out.
Respiration vs. Breathing Comparison:
- Process Type: Breathing is a physical, mechanical process of moving air. Respiration is a biochemical, cellular process.
- Location: Breathing occurs in the lungs and respiratory passages. Respiration occurs in the mitochondria of every cell in the body.
- Energy: Breathing consumes a small amount of energy. Respiration releases a large amount of energy from food.
- Enzymes: Breathing involves no enzymes. Respiration is a complex process that relies on numerous specific enzymes.
Four Major Respiratory Diseases:
- Asthma: A chronic inflammatory disease causing airway narrowing. Symptoms include wheezing, coughing, and chest tightness. It is often triggered by allergens or irritants.
- Bronchitis: Inflammation of the bronchial tubes, leading to a persistent cough with mucus. It can be acute (often viral) or chronic (often from smoking).
- Pneumonia: An infection of the alveoli, which fill with fluid or pus, impairing gas exchange. Caused by bacteria, viruses, or fungi, with symptoms like fever, chills, and cough.
- Tuberculosis (TB): A serious infectious bacterial disease primarily affecting the lungs. It is caused by Mycobacterium tuberculosis and can be fatal if not treated.
Pathway of Air: Air enters the nose, where it is filtered, warmed, and humidified. It then passes through the pharynx and into the larynx. From the larynx, it travels down the trachea, which is kept open by cartilage rings. The trachea splits into two bronchi, which enter the lungs and branch into smaller bronchioles. Finally, the air reaches the alveoli, tiny air sacs where the critical exchange of oxygen and carbon dioxide with the blood occurs.
Importance of the Diaphragm: The diaphragm is the primary muscle of respiration. It is a large, dome-shaped sheet of muscle located at the base of the thoracic cavity. It is innervated by the phrenic nerve. During inhalation, it contracts and flattens, dramatically increasing the vertical dimension of the chest cavity. This action is responsible for about 75% of the air movement in normal, quiet breathing. Its relaxation during exhalation allows the chest cavity to shrink, pushing air out.
Role of Pressure Differences in Breathing: Breathing operates on the principle of Boyle's Law, where pressure and volume are inversely related. During inhalation, the contraction of the diaphragm and intercostal muscles increases the lung volume, which decreases the intrapulmonary pressure to below atmospheric pressure, causing air to flow in. During exhalation, the relaxation of these muscles decreases lung volume, increasing the intrapulmonary pressure above atmospheric pressure, causing air to flow out. Any condition that prevents these volume changes, like a punctured lung, disrupts this pressure gradient and can cause breathing to fail.
Protective Mechanisms of the Respiratory System: The system has several lines of defense. The nose acts as a first-line filter with its hairs and mucus. The entire respiratory tract, from the trachea to the bronchi, is lined with a mucociliary escalator, where cilia continuously beat upward, moving mucus-trapped debris out of the lungs. Finally, powerful reflex actions like coughing and sneezing forcefully expel larger irritants from the pharynx, larynx, or trachea.
Respiratory and Circulatory System Relationship: These two systems are inextricably linked in a process of gas transport. The respiratory system acquires oxygen from the atmosphere and removes carbon dioxide from the body. The circulatory system, via the blood and heart, acts as the transport medium. Blood picks up oxygen in the lungs, delivers it to the body's tissues for cellular respiration, and picks up the waste product, carbon dioxide, to be transported back to the lungs for exhalation. A failure in one system (e.g., a heart attack or lung disease) will critically impair the function of the other.
Alveoli Structure and Function: Alveoli are the functional units of the lungs. They are microscopic, grape-like clusters of air sacs with incredibly thin walls (one cell thick) to facilitate rapid gas diffusion. Their effectiveness is enhanced by a massive total surface area (equivalent to a tennis court) and a dense network of surrounding capillaries, ensuring a minimal distance for gases to travel between air and blood. A substance called surfactant prevents the alveoli from collapsing during exhalation.
Asthma Explained: Asthma is a chronic condition where the airways become inflamed, swollen, and hypersensitive. When exposed to triggers (like pollen, dust, or cold air), the smooth muscles around the airways constrict (bronchospasm), and excess mucus is produced. This combination severely narrows the airways, making it difficult for air to move in and out, leading to the characteristic symptoms of wheezing, shortness of breath, and chest tightness.
Tuberculosis Explained: Tuberculosis is a contagious and potentially fatal infectious disease caused by the bacterium Mycobacterium tuberculosis. It is transmitted through airborne droplets from the coughs or sneezes of an infected person. While it primarily attacks the lungs, causing a chronic cough, fever, and weight loss, it can spread to other parts of the body. It is considered serious because the bacteria can remain dormant for years and become active later, and drug-resistant strains are a growing concern.
Pneumonia Analysis: Pneumonia is an inflammation of the lung tissue, specifically the alveoli, usually caused by infection. The infection leads to the air sacs filling with fluid or pus, which severely interferes with the ability of oxygen to diffuse into the bloodstream. This results in hypoxemia (low blood oxygen). Symptoms reflect this struggle, including high fever, chills, a productive cough, and significant difficulty breathing.
Lung Volumes and Capacities:
- Tidal Volume (TV): The amount of air moved in or out during a normal, quiet breath.
- Vital Capacity (VC): The maximum amount of air that can be forcefully exhaled after taking the deepest possible breath. It represents the total usable volume of the lungs.
- Residual Volume (RV): The amount of air that remains in the lungs even after a maximal exhalation. This volume ensures that the alveoli do not collapse completely.
Neural Control of Breathing: Breathing is controlled by the respiratory centers in the medulla oblongata and pons of the brainstem. The medulla sets the basic rhythm of breathing. These centers receive input from chemoreceptors that monitor the levels of oxygen, carbon dioxide, and pH in the blood. High CO2 levels are the primary stimulus for increasing the rate and depth of breathing. While the basic rhythm is involuntary, it can be temporarily overridden by conscious control from the cerebral cortex.
Environmental Factors on Respiratory Health:
- Pollution: Air pollutants like smoke, dust, and chemical fumes can irritate the airways, trigger asthma, and contribute to chronic diseases like COPD.
- Altitude: At high altitudes, the lower partial pressure of oxygen makes it harder to get enough oxygen, leading to shortness of breath and altitude sickness.
- Temperature & Humidity: Cold, dry air can irritate the airways and trigger bronchospasm in sensitive individuals.
Emergency Respiratory Responses:
- Breath-holding: This is a voluntary act controlled by the cerebral cortex, but it is limited by the buildup of CO2 in the blood, which eventually forces an involuntary breath.
- Choking: This occurs when an object blocks the trachea. The Heimlich maneuver is a first-aid technique to forcefully expel the object by creating a strong artificial cough.
- Artificial Respiration: (e.g., mouth-to-mouth) is used when a person has stopped breathing. It manually forces air into the lungs to provide oxygen until the person can breathe on their own again.
Age-Related Changes in Respiration: With age, the respiratory system becomes less efficient. The chest wall becomes more rigid, respiratory muscles weaken, and the elastic recoil of the lungs decreases. This leads to a reduction in vital capacity and makes it harder to cough effectively, increasing the risk of respiratory infections like pneumonia.
Respiratory System and pH Balance: The respiratory system plays a crucial role in maintaining the body's acid-base balance. Carbon dioxide combines with water in the blood to form carbonic acid. By adjusting the rate and depth of breathing, the body can regulate the amount of CO2 in the blood. For example, if the blood becomes too acidic, the breathing rate increases to blow off more CO2, thus reducing the acidity.
Respiratory Adaptations to Exercise: During exercise, the respiratory system makes immediate adjustments by increasing the rate and depth of breathing to meet the body's heightened demand for oxygen and to remove excess carbon dioxide. With long-term training, the respiratory muscles become stronger and more efficient, vital capacity may increase slightly, and the body becomes better at extracting oxygen from the air.
Smoking Effects on Respiratory System: Smoking is devastating to the respiratory system. It paralyzes and destroys the cilia, leading to a buildup of mucus (smoker's cough) and increased infections. It irritates the airways, causing chronic bronchitis, and destroys the delicate alveolar walls, leading to emphysema. It is also the leading cause of lung cancer.
Sleep-Related Breathing Disorders: Sleep apnea is a common disorder where a person repeatedly stops and starts breathing during sleep. The most common type, obstructive sleep apnea, occurs when the throat muscles relax and block the airway. These episodes of apnea lead to poor sleep quality, daytime sleepiness, and can increase the risk of high blood pressure, heart attack, and stroke.
Respiratory First Aid: For someone choking, the Heimlich maneuver is the standard response. For someone who has stopped breathing, cardiopulmonary resuscitation (CPR), which combines chest compressions with rescue breaths (artificial respiration), is critical to circulate oxygenated blood until emergency medical services arrive.
Occupational Respiratory Diseases: Many occupations expose workers to substances that can harm the lungs. For example, coal miners can develop black lung disease from coal dust. Construction workers exposed to asbestos can develop asbestosis and mesothelioma. Prevention involves proper ventilation, wearing protective masks, and minimizing exposure to harmful dusts and chemicals.
Future of Respiratory Health: The future will likely see challenges from emerging respiratory viruses (like new strains of influenza or coronaviruses) and the effects of climate change and pollution. Advances in treatment may include personalized medicine for conditions like asthma and cystic fibrosis, new antiviral drugs, and improved vaccine technologies. Prevention will remain key, focusing on smoking cessation, air quality control, and global surveillance for new pathogens.

The Respiratory System