Same chapter2 marksDifficulty: Medium
Distinguish between active and passive absorption of mineral salts by roots.
Absorption by Roots
3 marksDifficulty: Medium
Describe an experiment to demonstrate osmosis using a potato osmoscope.
Original Khojo Papers practice question — not from a past board paper.
Answer
A large potato is peeled at one end and hollowed out to form a cup, which is placed in a dish of water and half filled with concentrated sugar solution, and the initial level is marked. After some hours the level in the cavity has risen. Water has passed from the dish through the living potato cells into the more concentrated solution, which is osmosis. A boiled potato set up in the same way shows no rise.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The boiled potato is the control, and it shows that living cells are needed.
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From the same topic and chapter, at a similar level.
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Describe the structure of a root hair and state how it is adapted for absorption.
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Same chapter3 marksDifficulty: Medium
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