LIFE SCIENCE

Detailed explanation-1: -As discussed in Chapter 2, the plasma membranes of animal cells contain four major phospholipids (phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin), which together account for more than half of the lipid in most membranes.

Detailed explanation-2: -Four major phospholipids predominate in the plasma membrane of many mammalian cells: phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin.

Detailed explanation-3: -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-4: -The fundamental building blocks of all cell membranes are phospholipids, which are amphipathic molecules, consisting of two hydrophobic fatty acid chains linked to a phosphate-containing hydrophilic head group (see Figure 2.7).

Detailed explanation-5: -Phospholipids are major components of the plasma membrane, the outermost layer of animal cells.