HUMAN NUTRITION

Detailed explanation-1: -The lipid bilayer has been firmly established as the universal basis for cell-membrane structure. It is easily seen by electron microscopy, although specialized techniques, such as x-ray diffraction and freeze-fracture electron microscopy, are needed to reveal the details of its organization.

Detailed explanation-2: -The phospholipid bilayer is critical in maintaining the integrity of the cardiomyocyte, as it forms a permeability barrier that provides a physical interface between the inside and the outside of the myocyte. It also contains key enzymes and ion channels that regulate ionic gradients across the cell membranes.

Detailed explanation-3: -Phospholipids spontaneously form stable bilayers, with their polar head groups exposed to water and their hydrophobic tails buried in the interior of the membrane. Lipids constitute approximately 50% of the mass of most cell membranes, although this proportion varies depending on the type of membrane.

Detailed explanation-4: -The answer is e. Phosphatidylcholine and cholesterol. The phosphatidylcholine and cholesterol are the major components of a biological membrane. Phosphatidylcholine is a type of phospholipid molecule that is commonly found in the cell membrane or biological membrane.