Question 1: In the figure below ‘A’ shows a cell in the normal state and ‘B’
shows the
same cell after leaving it in a certain solution for a few minutes.
(i) Describe the change which has occurred in the cell as seen in B.
(ii) Give the technical term for the condition of the cell as reached in B and
as it was in A.
(iii) Define the process which led to this condition.
(iv) What was the solution-isotonic, hypotonic or hypertonic, in which the cell
was kept ?
(v) How can the cell in B, be brought back to its original condition ?
(vi) Name the parts numbered 1 to 3.
Answer:
(i) Exosmosis (exit of water) has resulted in the shrinkage of the protoplasm
of cell B.
(ii) Plasmolysis and deplasmolysis.
(iii) When plant cells are kept in a hypertonic solution, exosmosis takes
place. This process
is called plasmolysis.
(iv) Hypertonic solution.
(v) The cell in B can be brought back to its original condition by placing it in a
drop of
distilled water.
(vi) 1. Cell wall, 2. Plasma membrane, 3. Chloroplast.
Question 2: The alongside diagram A shows a root hair growing through the
soil particles.
The diagram B is the root hair of an aquatic plant.
,(i) Name the parts 1,2,3.
(ii) Name two substances which enter the root hair. What are their uses ?
(iii) By what process do these substances enter the root hair ?
(iv) Account for the different shapes of root hairs in the two diagrams.
Answer: (i) 1-Nucleus. 2-Cell wall. 3-Cytoplasm of the root hair cell.
(ii) 1. Water: Carries minerals to the plant.
2. Minerals : They are needed for healthy plant growth.
(iii) Osmosis.
(iv) In the Fig. A, the root hair has to pass through the soil particles and as
such they are
not straight. In the Fig. B, the root hair has no obstruction in water, and as
such it grows
straight.
Question 3: Given below is the diagram of a cell as seen under the
microscope after
having been placed in a solution :
, (i) What is the technical terms used for the state/condition of the cell given
above ?
(ii) Give the technical term for the solution in which the cell was placed.
(iii) Name the parts numbered 1 to 4.
(iv) Is the cell given above a plant cell or an animal cell ? Give two reasons in
support of
your answer as evident from the diagram.
(v) What would you do to bring this cell back to its original condition.
Answer: (i) Plasmolysis
(ii) Hypertonic solution
(iii) (1) Nucleus, (2) Sugar drops, (3) Small vacuole, (4) Large vacuole.
(iv) Plant cell (1) Presence of cell wall, (2) Presence of large vacuole.
(v) It has to be placed in a hypotonic solution.
Question 4: The below diagram represents a plant cell after being placed in a
strong sugar
solution. Guidelines 1 to 5 indicate the following :
1. Cell wall
2. Plasma membrane.
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.
Answer:
(i) Flaccid.
(ii) Plasma membrane.
(iii) If the cell had been placed in distilled water it remains in a fully
distended condition.
shows the
same cell after leaving it in a certain solution for a few minutes.
(i) Describe the change which has occurred in the cell as seen in B.
(ii) Give the technical term for the condition of the cell as reached in B and
as it was in A.
(iii) Define the process which led to this condition.
(iv) What was the solution-isotonic, hypotonic or hypertonic, in which the cell
was kept ?
(v) How can the cell in B, be brought back to its original condition ?
(vi) Name the parts numbered 1 to 3.
Answer:
(i) Exosmosis (exit of water) has resulted in the shrinkage of the protoplasm
of cell B.
(ii) Plasmolysis and deplasmolysis.
(iii) When plant cells are kept in a hypertonic solution, exosmosis takes
place. This process
is called plasmolysis.
(iv) Hypertonic solution.
(v) The cell in B can be brought back to its original condition by placing it in a
drop of
distilled water.
(vi) 1. Cell wall, 2. Plasma membrane, 3. Chloroplast.
Question 2: The alongside diagram A shows a root hair growing through the
soil particles.
The diagram B is the root hair of an aquatic plant.
,(i) Name the parts 1,2,3.
(ii) Name two substances which enter the root hair. What are their uses ?
(iii) By what process do these substances enter the root hair ?
(iv) Account for the different shapes of root hairs in the two diagrams.
Answer: (i) 1-Nucleus. 2-Cell wall. 3-Cytoplasm of the root hair cell.
(ii) 1. Water: Carries minerals to the plant.
2. Minerals : They are needed for healthy plant growth.
(iii) Osmosis.
(iv) In the Fig. A, the root hair has to pass through the soil particles and as
such they are
not straight. In the Fig. B, the root hair has no obstruction in water, and as
such it grows
straight.
Question 3: Given below is the diagram of a cell as seen under the
microscope after
having been placed in a solution :
, (i) What is the technical terms used for the state/condition of the cell given
above ?
(ii) Give the technical term for the solution in which the cell was placed.
(iii) Name the parts numbered 1 to 4.
(iv) Is the cell given above a plant cell or an animal cell ? Give two reasons in
support of
your answer as evident from the diagram.
(v) What would you do to bring this cell back to its original condition.
Answer: (i) Plasmolysis
(ii) Hypertonic solution
(iii) (1) Nucleus, (2) Sugar drops, (3) Small vacuole, (4) Large vacuole.
(iv) Plant cell (1) Presence of cell wall, (2) Presence of large vacuole.
(v) It has to be placed in a hypotonic solution.
Question 4: The below diagram represents a plant cell after being placed in a
strong sugar
solution. Guidelines 1 to 5 indicate the following :
1. Cell wall
2. Plasma membrane.
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.
Answer:
(i) Flaccid.
(ii) Plasma membrane.
(iii) If the cell had been placed in distilled water it remains in a fully
distended condition.
