Q. Keeping in view the 'fluid mosaic model' for the structure of cell membrane, which one of the following statements is correct w.r.t. the movement of lipids and proteins from one lipid monolayer to the other (described as flip-flop movement)?
A) Neither lipids nor proteins can flip-flop
B) Both lipids and proteins can flip-flop
C) While lipids can rarely flip-flop, proteins cannot
D) While proteins can flip-flop, lipids cannot
Explanation
[Solution from source] Membrane lipids occasionally move from one leaflet to the other (transverse diffusion), though this is slow and rare. Proteins, with their large hydrophilic domains, cannot cross the hydrophobic core, so they move only laterally. Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.