Class 11 NEET Biology Cell - The Unit of Life Questions Part 1

(b) : Plasma membrane consists of lipids (20-79 %), proteins (20-70 %), carbohydrates (1-5 %) and water (20 %) . Lipid molecules possess both hydrophobic and hydrophilic ends and are thus arranged in the form of lipid bilayer. Most common lipid of the bilayer is phospholipid. Protein molecules occur at places both inside (intrinsic proteins) and on the outer side (extrinsic proteins) of the phospholipid bilayer.