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प्रश्न
The diagram below represents a layer of epidermal cells showing a fully grown root hair. Study the diagram and answer the questions that follow:
Mention one distinct difference between the parts labelled A and B.
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उत्तर
|
Cell wall |
Cell membrane |
|
The cell wall of a root hair is freely permeable and allows both salt and water to pass through. |
The cell membrane of a root hair is semi-permeable and does not allow large dissolved salt molecules to pass through. |
संबंधित प्रश्न
Choose the correct answer:
Which one is semi-permeable?
Choose the correct answer:
Wilting of plants occurs when ____________
Differentiate between the following
Permeable and Semi-permeable membrane.
A thin strip of epidermal cells from the fleshy scales of an onion bulb was examined in a drop of water, under a microscope. All the epidermal cells looked alike and the figure alongside represents one of them. The thin strip was then transferred to a drop of strong sugar solution and re-examined under the microscope after about five minutes.
(i) Make a sketch of one of the epidermal cells, as it might appear after immersion in a strong sugar solution. Label any two parts which have undergone a change.
(ii) Give the scientific term for the change shown in Q.(i) above.
(iii) What would you do to bring this cell back to its original condition?
(iv) Give the scientific term used for the recovery of the cell as a result of the step taken in Q.(iii) above.
Column ‘II’ is a list of items related to ideas in Column ‘I’. Match the term in Column ‘II’ with a suitable idea given in Column ‘I’.
| Column I | Column II |
| (i) Diffusion | (a) The exit or flow of water from the cell to the outer environment. |
| (ii) Xylem | (b) The shrinkage of protoplasm when the cell is kept in a hypertonic solution. |
| (iii) Root pressure | (c) The tissue through which water and mineral salts move upward in a plant. |
| (iv) Isotonic solution | (d) Two solutions which have equal osmotic pressure. |
| (v) Exosmosis | (e) The process by which the molecules of perfume spread in the room when the bottle is open. |
| (vi) Osmosis | (f) The process by which roots absorb water from the soil. |
| (vii) Plasmolysis | (g) The pressure by which water rises up to some feet in a lofty tree. |
| (viii) Hypotonic solution | (h) The concentration of the solution when lower than that of the cell sap. |
A thin strip of epidermal cells of a leaf was observed in a drop of water. They all looked turgid and normal.
(a) Draw a diagram of such a cell.
(b) Draw a diagram of a cell if this strip is transferred to a strong concentrated solution of sugar. What is term used for the effect on the cells ?
Multiple Choice Question:
In soil, water available for absorption by root is ______.
Define: Root hair
In soil which of the following type of water is available for absorption by plant roots?
Root hair occurs in the zone of ____________.
