Question

According to fluid mosaic model, plasma membrane is composed of

• A. Phospholipids and oligosaccharides
• B. Phospholipids and hemicellulose
• C. Phospholipids and integral proteins
• D. Phospholipids, extrinsic proteins and intrinsic proteins

Answer 1

The correct option is D Phospholipids, extrinsic proteins and intrinsic proteins

• The fluid mosaic model of the biomembrane or cell membrane was proposed by SJ Singer and GL Nicolson in the year 1972.
  
• According to this model, the transmembrane proteins are embedded within the phospholipid bilayer.
• Transmembrane proteins are of two types-

1. Extrinsic membrane proteins- are present outside the membrane which bound to the lipid layer by weak molecular forces.
2. Intrinsic membrane proteins- are completely embedded in the membrane.

• So, the correct answer is 'Phospholipids, extrinsic proteins and intrinsic proteins'.