Question

Which of the following statements is correct?
A) Cell membrane is involved only in Exosmosis.
B) Cell membrane is involved only in endosmosis.
C) Cell membrane is involved both in Exosmosis and endosmosis.
D) None of the above.

Answer 1

Osmosis is a process in which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one.

Complete answer:
Let us analyse the options to find the correct answer.
Option A: cell membrane is a semi permeable membrane which allows certain molecules and ions through it. When the concentration of the medium in which the cell is placed is more than the concentration of the cell content, then water comes out from the cell and causes Exosmosis. Therefore, this is the incorrect option.
Option B: cell membrane is semi permeable membrane which allows certain molecules and ions through it. When the concentration of the medium in which the cell is placed is less than the concentration of the cell content, and then water comes out from the cell and causes Endosmosis. Therefore, this is the incorrect option
Option C: Osmosis is the movement of a solvent (water in the living system) from a region of its high concentration (less concentrated solution) to a region of its low concentration (more concentrated solution) across a semipermeable membrane. When water flows inside a cell from the surrounding solution, the process is called endosmosis. As a result of endosmosis, the cell swells. When water moves out of the cell into the surrounding solution, the process is called Exosmosis. As a result of Exosmosis, cells shrink and are called as plasmolyzed. Therefore, this is the correct option.
Option D: As one of the options is correct, therefore, this is the incorrect option.
Thus, the correct option is C) Cell membrane is involved both in Exosmosis and endosmosis.

Note: Reverse osmosis (RO) is a water purification process that uses a partially permeable membrane to remove ions, unwanted molecules and larger particles from drinking water.