LIFE SCIENCE

Detailed explanation-1: -Like all other cellular membranes, the plasma membrane consists of both lipids and proteins. The fundamental structure of the membrane is the phospholipid bilayer, which forms a stable barrier between two aqueous compartments.

Detailed explanation-2: -The lipid bilayer of many cell membranes is not composed exclusively of phospholipids, however; it often also contains cholesterol and glycolipids. Eucaryotic plasma membranes contain especially large amounts of cholesterol (Figure 10-10)-up to one molecule for every phospholipid molecule.

Detailed explanation-3: -Biological membranes consist of proteins inserted into a lipid bilayer. Integral membrane proteins are embedded in the membrane, usually via -helical regions of 20 to 25 hydrophobic amino acids.

Detailed explanation-4: -Carbohydrates attached to lipids (glycolipids) and to proteins (glycoproteins) extend from the outward-facing surface of the membrane. The principal components of a plasma membrane are lipids (phospholipids and cholesterol), proteins, and carbohydrates.