Class XI Practical: Spotting

Objective

To identify and draw various biological specimens, slides, and experimental setups, and infer their characteristics or principles.

Guidelines

For each item presented (slide, specimen, or experimental setup):

1. Identification: Correctly identify the given item.
2. Drawing: Make a neat, labeled diagram of the identified item. For slides, draw what is observed under the microscope. For specimens, draw the external features. For experimental setups, draw the arrangement of apparatus.
3. Observation: Note down key observable features or results.
4. Inference/Comment: Briefly explain the biological significance, principle demonstrated, or classification of the item.

Items for Spotting

Slides/Specimens

• Meiosis stages (prepared slides)
• Mammalian blood cells (prepared slides)
• Bacteria (prepared slides)
• Spirogyra (specimen/slide)
• Amoeba (specimen/slide)
• Yeast (specimen/slide)
• Liverworts (specimen)
• Moss (specimen)
• Fern (specimen)
• Pinus (specimen)
• Mushroom (specimen)
• Monocot (e.g., bamboo - specimen)
• Dicot (e.g., Petunia - specimen)
• Sponge (specimen)
• Hydra (specimen)
• Tapeworm (specimen)
• Leech (specimen)
• Silkworm (specimen)
• Rohu fish (specimen)

Experimental Setups

• Osmosis: (e.g., Thistle funnel experiment, potato osmoscope)
  • Identify: The setup demonstrating osmosis.
  • Draw: Labeled diagram of the setup.
  • Observation: Note changes in liquid levels or cell appearance.
  • Inference: Explain the movement of water across a semi-permeable membrane.
• Transpiration: (e.g., Bell jar experiment with potted plant, Ganong's potometer)
  • Identify: The setup demonstrating transpiration.
  • Draw: Labeled diagram of the setup.
  • Observation: Note water loss or condensation.
  • Inference: Explain water vapor loss from plant surfaces.
• Photosynthesis: (e.g., Hydrilla experiment for O₂ evolution, Moll's half-leaf experiment)
  • Identify: The setup demonstrating photosynthesis.
  • Draw: Labeled diagram of the setup.
  • Observation: Note gas bubble evolution or starch presence.
  • Inference: Explain the process of photosynthesis and its requirements.
• Transpiration Pull: (e.g., Cohesion-tension model demonstration)
  • Identify: The setup demonstrating transpiration pull.
  • Draw: Labeled diagram of the setup.
  • Observation: Note water movement.
  • Inference: Explain the role of transpiration in water ascent in plants.