4. Biomolecules

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.

Macronutrients .a. include carbohydrates and vitamins;b. should make up a small percentage of a healthful diet;c. are essential in minute amounts to help enzymes function;d. include carbohydrates, fats, and proteins;e. are synthesized by cells and not necessary to obtain from the diet

Which of the following is true of unsaturated fats?a. They are more common in animals than in plants.b. They have double bonds in their fatty acid chains.c. They generally solidify at room temperature.d. They contain more hydrogen than do saturated fats having the same number of carbon atoms.

What makes a fatty acid an acid?a. It does not dissolve in water.b. It is capable of bonding with other molecules to form a fat.c. It has a carboxyl group that can donate an H+ to a solution.d. It contains only two oxygen atoms.

Cooking oil lipids consist of long, unsaturated hydrocarbon chains. Would you expect these molecules to form membranes spontaneously? Why or why not? Describe, on a molecular level, how you would expect these lipids to behave in water.

Which of the following terms is least like the others?a. monosaccharide;b. phospholipid;c. fat;d. steroid;e. lipid

The main constituents of the plasma membrane are .a. carbohydrates and lipids;b. proteins and phospholipids;c. fats and carbohydrates;d. fatty acids and nucleic acids

Unsaturated fatsa. have double bonds in their fatty acid chains.b. have fewer fatty acid molecules per fat molecule.c. are associated with greater health risks than are saturated fats.d. are more common in animals than in plants.

A fat molecule consists of .a. carbohydrates and proteins;b. complex carbohydrates only;c. saturated oxygen atoms;d. a carbon skeleton and fatty acids

Another aspect of the Nurses' Health Study looked at the percentage of change in the risk of coronary heart disease associated with substituting one dietary component for another. These results estimated that replacement of 5% of energy from saturated fat in the diet with unsaturated fats would reduce the risk of heart disease by 42%, and that the replacement of 2% of energy from trans fat with unsaturated fats would reduce the risk by 53%. Explain what these numbers mean.