Assertion (A): The cell membrane is described by the fluid mosaic model. Reason (R): The phospholipid bilayer is fluid, and proteins are embedded like a mosaic. MCQ with Answer and Explanation

Assertion (A): The cell membrane is described by the fluid mosaic model. Reason (R): The phospholipid bilayer is fluid, and proteins are embedded like a mosaic.
A. A is false, but R is true.
B. Both A and R are true, but R is not the correct explanation of A.
C. A is true, but R is false.
D. Both A and R are true, and R is the correct explanation of A.
Answer: Option D
Solution (By JKExamLibrary)
The fluid mosaic model, proposed by Singer and Nicolson in 1972, accurately describes the plasma membrane. The phospholipid bilayer has a fluid consistency, allowing lateral movement of lipids and proteins. Proteins float within or on this bilayer, forming a mosaic pattern. Thus, the reason correctly explains the assertion.

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