Biology
The figure given below shows the epidermal cells of an onion bulb. This cell was then transferred to a drop of sugar solution.
(i) Draw a well labelled diagram of the epidermal cell as it would appear after immersion in a strong sugar solution.
(ii) What scientific term is used for the changes as shown in (i) above ?
(iii) What should be done to restore the cell back to its original condition ?
(iv) Give the scientific term for the recovery of the cell as a result of the step taken in (iii) above.
(v) Define the term osmosis.
Answer
(i) Diagram of the plasmolysed epidermal cell after immersing it in a strong sugar solution is shown below:
(ii) Plasmolysis is technical term used for the above change.
(iii) To restore the cell back to its original condition, it must be placed in hypotonic solution immediately after it gets plasmolysed.
(iv) Deplasmolysis is technical term used for recovery of the cell as a result of the step taken in (iii) above.
(v) Osmosis is the movement of water molecules from their region of higher concentration (dilute solution or with a lower solute concentration) to their region of lower concentration (concentrated solution or with a higher solute concentration) through a semi permeable membrane.
Related Questions
(i) Draw a well labelled diagram to show the anaphase stage of mitosis in a plant cell having four chromosomes.
(ii) State any two harmful effects of acid rain.
(iii) Expand the following biological abbreviations :
- NADP
- ACT
Briefly explain the following terms:
(i) Genes.
(ii) Cytokinesis in plant cells.
(iii) Guttation.
(iv) Diabetes insipidus.
(v) Disinfectants.
Give biological reasons for the following :
Throat infections can lead to ear infections.
Give biological reasons for the following :
The hand automatically shows the direction to turn a cycle without thinking.