Chapter 5 Mastering Biology

as a component of animal cell membranes

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

nucleotide

Nucleic acid polymers are made up of ___________ monomers.

amino acid

Protein polymers are made up of ___________ monomers.

d. saturated fat

This figure is an example of a(n) _____. a. steroid b. protein c. unsaturated fat d. saturated fat e. nucleic acid

c. RNA

Which of these is NOT a lipid? a. steroids b. wax c. RNA d. cholesterol e. phospholipid

e. olive oil

Which of these is rich in unsaturated fats? a. beef fat b. lard c. a fat that is solid at room temperature d. butter e. olive oil

simple sugar

Carbohydrate polymers are made up of ________________ monomers.

Yes. Nonpolar molecules aren't compatible with water.

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

2

How many fatty acids are in a phospholipid?

1

How many hydrogen atoms can be attached to carbon B?

(b) Low solubility in water.

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).

negative charge to interact with water place to attach another small charged molecule

What functional feature(s) does the phosphate group contribute to the structure of a phospholipid? Select all that apply. a. negative charge to interact with water b. nonpolar group that avoids water c. place to attach another small charged molecule d. place where bonds can form between adjoining phospholipids e. place to attach fatty acids

hydrophilic and hydrophobic interactions with water

What holds phospholipids together in a bilayer formation? a. hydrophilic and hydrophobic interactions with water b. ionic interactions between phospholipid tails c. interaction of cis-double bonds in tails with polar heads d. covalent bonds between polar heads

d. dehydration

What is another name for a condensation reaction? a. water formation b. hydrolysis c. catabolism d. dehydration e. monomerization

Hydrolysis

What is the name of the process during which a bond between two monomers is broken? a. combustion b. condensation c. hydrolysis d. dehydration

B and C

Which functional group(s) shown below is (are) present in all amino acids?

a. A fat molecule is less soluble in water because it has three non-polar fatty acids and no polar or charged head like a phospholipid has.

Which molecule is less soluble in water--a fat or a phospholipid? Why? a. A fat molecule is less soluble in water because it has three non-polar fatty acids and no polar or charged head like a phospholipid has. b. A phospholipid is less soluble in water because even though it has one end that is hydrophilic, the end that is hydrophobic is larger. c. A fat molecule is less soluble in water because it has more carbons and hydrogens than a phospholipid. d. A phospholipid is less soluble in water because it is smaller than a fat molecule.