Question

As per fluid mosaic model, lipids and integral proteins can diffuse randomly. The model has been modified in several aspects. Which of the following statements is incorrect?

Answer 1

Option A
Protein of cell membrane can travel within lipid bilayer.

Elaboration:
The quasi-fluid nature of the lipid allows the lateral movement of the proteins through the lipid bilayer. Hence, statement (A) is true.

Option B
Protein of cell membrane can undergo flip-flop movement in lipid bilayer.

Elaboration:
The movement of the lipid from one side of the membrane to the other side in a vertical manner is called the flip-flop movement. This movement does not occur in the proteins embedded in the lipid bilayer. Hence, statement (B) is the incorrect statement.

Option C
Proteins can remain confined within certain domains of the membrane.

Elaboration:
There are specific domains inside the lipid bilayer in which the proteins remain confined. This condition occurs in all types of membrane proteins. Hence, statement (C) is true.

Option D
Many proteins remain completely embedded within lipid bilayer.

Elaboration:
Integral membrane proteins remain completely embedded inside the lipid bilayer. Hence, statement (D) is true.

Final answer
$\left(B\right)$ Protein of cell membrane can undergo flip-flop movement in lipid bilayer