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Question
What is toxicity ?
Solution
It refers to the kind of external osmotic environment of a cell or it refers to the type of solution outside the cell.
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RELATED QUESTIONS
What part is played by the cell wall?
The diagram given below represents a plant cell after being placed in a strong sugar solution. Guidelines 1 to 5 indicate the following:
1. Strong sugar solution
2. Cell wall
3. Protoplasm
4. Large vacuole
5. Nucleus
Study the diagram and answer the questions that follow:
(i) What is the state of the cell shown in the diagram?
(ii) Name the structure which acts as a selectively permeable membrane.
(iii) If the cell had been placed in distilled water instead of strong sugar solution which feature would not have been present?
(iv) If the cell in the diagram possessed chloroplasts where would these be present?
(v) Name any one feature of this plant cell which is not present in animal cells.
Choose the correct answer:
Exudation or bleeding is associated with ___________
Choose the correct answer:
Wilting of plants occurs when ____________
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.
Name the following:
Root hairs are the extension of which cells.
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. |
Epiphytic plants like orchids absorb water vapours from air with the help of epiphytic roots having special tissue called ____________.
____________plants like orchids absorb water vapours from air with the help of epiphytic roots having special tissue called velamen.
Which plant does tissue transport water and minerals from the roots to the leaf?