Question

Read the assertion and reason carefully to mark the correct option in question


Assertion: A cell membrane shows quasi-fluid behaviour.

Reason: A membrane is a mosaic or composite of diverse lipids and proteins.

• A. If assertion is true but reason is false.
• B. If both assertion and reason are true but the reason is not the correct explanation of the assertion.
• C. If both assertion and reason are false.
• D. If both assertion and reason are true and the reason is the correct explanation of the assertion.

Answer 1

The correct option is D If both assertion and reason are true and the reason is the correct explanation of the assertion.

Elaboration:

According to the fluid mosaic model that explains the structure of plasma membrane, the cell membrane is quasi-fluid in nature. This is because the plasma membrane consists of fatty acid chains that exhibit lateral and flip-flop movements. Whereas the proteins in the plasma membrane appear as the mosaic with limited movement. Thus assertion and reason are true and the reason is the correct explanation for the assertion.

Final answer: (A) If both assertion and reasons are true and the reason is the correct explanation of the assertion.