AP BIOLOGY

Detailed explanation-1: -Phospholipids (PL) are a group of polar lipids that consist of two fatty acids, a glycerol unit and a phosphate group which is esterified to an organic molecule (X) such as choline, ethanolamine, inositol, etc.

Detailed explanation-2: -A phospholipid is a lipid made of glycerol, two fatty acid tails, and a phosphate-linked head group. Biological membranes usually involve two layers of phospholipids with their tails pointing inward, an arrangement called a phospholipid bilayer.

Detailed explanation-3: -A phospholipid consists of a hydrophilic (water-loving) head and hydrophobic (water-fearing) tail. In water, phospholipids spontaneously form a double layer called a lipid bilayer, in which the hydrophobic tails of phospholipid molecules are sandwiched between two layers of hydrophilic heads.

Detailed explanation-4: -Key Points. Phospholipids consist of a glycerol molecule, two fatty acids, and a phosphate group that is modified by an alcohol.

Detailed explanation-5: -Triglycerides. A fat molecule is a type of lipid that consists of three fatty acid molecules connected to a 3 carbon glycerol backbone, as shown on the right. The three fatty acids can be different from one another.