Question

Which of the following theories explain that plasma membrane is selectively permeable:

• A. Unit membrane theory
• B. Cascade theory
• C. Sandwich theory
• D. Fluid Mosaic theory

Answer 1

Answer:

D. Fluid Mosaic theory

• The fluid mosaic model of cell membrane was first proposed by S.J. Singer and Garth L. Nicolson in 1972.

• It describes the structure of cell membranes where a flexible lipid layer is spread with large protein molecules that act as channels through which other molecules enter and exit any cell.

• According to this model, the components of a membrane such as proteins or glycolipids, form a mobile mosaic in the fluid-like environment created by a sea of phospholipids.

• There are restrictions to lateral movements, and subdomains within the cell membrane have distinct functions.