BIO 150 1.5

What do DNA, proteins, and fats have in common? -They are polymers. -They are polar. -They contain carbonyl groups. -They contain nitrogen. -They contain phosphorus.

They contain carbonyl groups.

Dr. Haxton told one of his students, "To move in the bloodstream, fats need the help of phospholipids." What would a good student say? -You have it backwards. Fats help phospholipids to travel. -Not so. Fats are small enough to travel easily without help. -Sorry, Dr. Haxton! Help comes from cholesterol, not phospholipids. -Yes. Nonpolar molecules aren't compatible with water. -Right. Fats are too polar to travel alone in water.

Yes. Nonpolar molecules aren't compatible with water.

A function of cholesterol that does not harm health is its role _____. -as a component of animal cell membranes -in calcium and phosphate metabolism -All of cholesterol's effects cause the body harm. -the most abundant male sex hormone -as the primary female sex hormone

as a component of animal cell membranes

Which of these is rich in unsaturated fats? -butter -lard -a fat that is solid at room temperature -beef fat -olive oil

olive oil

The most unsaturated fats have ... -the longest hydrocarbon tails. -the fewest double bonds. -the most double bonds. -the highest ratio of H to C. -the shortest hydrocarbon tails.

the most double bonds.

A food company hydrogenated a barrel of fat. The treatment ... (a) made the fat less fluid. (b) made the fat less saturated. (c) lengthened the fat tails. (d) put more bends (kinks) in the fat tails. Both (a) and (d).

(a) made the fat less fluid.

What do fats, steroids, and waxes have in common? (a) Moderate polarity. (b) Low solubility in water. (c) They occur in membranes. Both (a) and (c). Both (b) and (c).

(b) Low solubility in water.

The presence of many C-C and C-H bonds causes fats to be ... (a) rich in energy. (b) insoluble in water. (c) low in energy. Both (a) and (b). Both (b) and (c).

Both (a) and (b).

Triglycerides vary with respect to the number of ... (a) hydrocarbon tails. (b) C atoms in the tails. (c) double bonds in the tails. Both (b) and (c). All of the above.

Both (b) and (c).

Which of these is NOT a lipid? -RNA -cholesterol -steroids -phospholipid -wax

RNA

In fat synthesis,________and fatty acids combine to make fats plus________. -phosphate; glycerol -glycerol; water -esters; phosphate -glucose; phosphate -esters; water

glycerol; water

In the reaction that builds a fat,________ groups react with ________ groups. -sulfhydryl; carboxyl -hydroxyl; carboxyl -hydroxyl; phosphate -phosphate; amino -carboxyl; amino

hydroxyl; carboxyl