High cholesterol levels are considered a major risk factor for heart disease. If it is so bad for humans, why does the body make cholesterol in the first place?

Nutritionally, saturated triacylglycerols are considered to be less healthful than unsaturated triacylglycerols. What is the difference between them?

The lipids that form the main structural component of cell membranes are __________.

If a small droplet of triacylglycerol molecules is suspended in water, the fat molecules form a "ball of spaghetti" with no particular orientation. But if a droplet of phospholipid molecules is put in water, all the molecules point outward, toward the water. Phospholipids are forced into this orientation because phospholipids have __________.

The sex hormones estradiol and testosterone belong to which class of molecules?

Manufacturers make vegetable oils solid or semisolid at room temperature by __________.

Some lipids are formed when fatty acids are linked to glycerol. These subunits are linked together by __________.

The fatty acid tails of a phospholipid are __________ because they __________.

How do the phospholipids in archaea differ from those in other cells?a. They have tails made of unsaturated fatty acids instead of saturated fatty acids.b. They do not contain hydrocarbon chains.c. They have isoprenoid tails instead of fatty acid tails.d. They have two hydrocarbon chains instead of three hydrocarbon chains.