Biology
The diagram below represents a layer of epidermal cells showing a fully grown root hair. Study the diagram and answer the questions that follow:
(a) Name the parts labelled A, B, C and D.
(b) The root hair cell is in a turgid state. Name and explain the process that caused this state.
(c) Mention one distinct difference between the parts labelled A and B.
(d) Draw a diagram of the above root hair cell as it would appear when a concentrated solution of fertilizers is added near it.
Roots Absorption
ICSE
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Answer
(a) The parts labelled A, B, C and D are:
- A → Cell wall
- B → Cell membrane
- C → Cytoplasm
- D → Nucleus
(b) A root hair gets turgid because of the absorption of water from the surrounding. Absorption of water by root hair is achieved by the process of Osmosis. Root hairs contain cell sap which has a higher concentration of salts as compared to the outside soil water. This causes the water from the surrounding to move in because of endosmosis and in the process the root hair gets turgid.
(c) The cell wall of a root hair is freely permeable and allows both salt and water to pass through whereas the cell membrane of a root hair is semi-permeable and does not allow large dissolved salt molecules to pass through.
(d) Below is the diagram of the root hair cell as it would appear when a concentrated solution of fertilizers is added near it:
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The diagram given below represents an experimental set-up to demonstrate a certain process. Study the same and answer the questions that follow:
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(d) What control experiment can be set up for comparison?
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(f) Name any other material that can be used instead of parchment paper in the above experiment.
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