[Test Bank] Biochemistry: A Short Course 4th Edition by Tymoczko
1. Molecules that are readily soluble in water are considered:
2. The interaction that is described by Coulomb's law is called:
3. What would be the solubility of a salt in a solvent with a low dielectric constant?
4. Hydrophobic molecules are driven together by:
c. 	van der Waals interactions.
e. 	hydrogen bonds.
5. The protein that interacts with both water and the hydrophobic regions of the membrane is considered:
6. Protonation of a base yields its:
a. 	conjugate molecule.
b. 	conjugate base.
c. 	conjugate acid.
d. 	ionized derivative.
e. 	ionized base.
7. An organic acid ionizes to form a conjugate base and:
c. 	a hydroxyl ion.
d. 	a proton.
e. 	hydrogen peroxide.
8. Gastroesophageal reflux disease is a common example of a pathological change in:
a. 	pKa of acetic acid.
b. 	hydrogen bonds in a key digestive enzyme.
c. 	protein structure.
d. 	water content in cells.
e. 	pH level.
9. What is the pH of human blood?
10. Choose the functional group that CANNOT form a hydrogen bond with water.
a. 	carbonyl group
b. 	amino group
c. 	aromatic ring
d. 	alcohol group
e. 	sulfhydryl group
11. Which combination can associate to form a hydrogen bond?
a. 	N–H and O
b. 	N–H and S
c. 	O–H and P
d. 	C=O and S
e. 	C=O and P
12. What is the typical length of noncovalent bonds?
a. 	0.4 angstroms
b. 	4 angstroms
c. 	40 angstroms
d. 	4 nm
e. 	0.04 nm
13. In a typical cell, the water content is about:
14. Oxygen is an electronegative atom. That means that in a molecule of water the:
a. 	electrons of covalent bonds spend more time near the oxygen atom than near the hydrogen atoms.
b. 	electrons of covalent bonds spend more time near the hydrogen atoms than near the oxygen atom.
c. 	electrons of bonds are located closely to the hydrogen atoms.
d. 	electrons of bonds are located closely to the oxygen atom.
e. 	bonds joining the hydrogen atoms to the oxygen atom are noncovalent.
15. What does it mean that liquid water has a partly ordered structure?
a. 	There are van der Waals interactions between water molecules.
b. 	Hydrogen-bonded clusters of molecules are continually being formed and broken apart in liquid water.
c. 	In the physiological range of temperatures liquid water can undergo phase transition to gas that is completely unordered and to ice that is completely ordered.
d. 	There is Brownian motion of water molecules.
e. 	Water molecules can form hydrogen bonds with polar molecules but not with nonpolar molecules.
16. How many neighboring water molecules are hydrogen-bonded on average to one water molecule in a sample of pure water?
17. What type of interactions is NOT a weak interaction?
a. 	nuclear interactions
b. 	salt bridges
c. 	van der Waals interactions
d. 	ionic bonds
e. 	hydrogen bonds
18. What is the amount of energy needed to apply a 1-newton force over a distance of 1 angstrom?
a. 	1010 J
b. 	10–10 J
c. 	1 J
d. 	10 J
e. 	1 kcal
19. What is the amount of energy needed to raise the temperature of 2 kilograms of water from 14.5°C to 15.5°C?
a. 	2 J
b. 	2 kJ
c. 	2 cal
d. 	20 cal
e. 	2 kcal
20. How does Coulomb's energy depend on the distance (r) between the two interacting corpuscles?
a. 	directly proportional to r
b. 	directly proportional to r2
c. 	inversely proportional to r
d. 	inversely proportional to r2
e. 	directly proportional to 2r
21. What factor does NOT affect electrostatic interaction according to Coulomb's law?
a. 	the charges on the two interacting atoms
b. 	a change in entropy if the interaction occurs
c. 	the distance between the two interacting atoms
d. 	the dielectric constant of the medium
e. 	presence and concentration of other charged corpuscles in the medium
22. How much weaker are hydrogen bonds as compared to covalent bonds?
a. 	from 2 to 10 times
b. 	from 20 to 50 times
c. 	from 100 to 1000 times
d. 	from 1000 to 10,000 times
e. 	from 10,000 to a million times