Chemistry of Life Review ____ 1. Different atomic forms of ... - Teacher

Chemistry of Life Review
____ 1. Different atomic forms of an element contain the same number of protons but a different number of neutrons. What are
these different atomic forms called?
a. ions
b. isotopes
c. neutronic atoms
d. isomers
e. radioactive atoms
____ 2. When two atoms are equally electronegative, they will interact to form
a. equal numbers of isotopes.
b. ions.
c. polar covalent bonds.
d. nonpolar covalent bonds.
e. ionic bonds.
____ 3. Which of the following results from a transfer of electron(s) between atoms?
a. nonpolar covalent bond
b. polar covalent bond
c. ionic bond
d. hydrogen bond
e. hydrophobic interaction
____ 4. Which of the following explains most specifically the attraction of water molecules to one another?
a. nonpolar covalent bond
b. polar covalent bond
c. ionic bond
d. hydrogen bond
e. hydrophobic interaction
____ 5. Van der Waals interactions result when
a. hybrid orbitals overlap.
b. electrons are not symmetrically distributed in a molecule.
c. molecules held by ionic bonds react with water.
d. two polar covalent bonds react.
e. a hydrogen atom loses an electron.
____ 6. Which of the following is not considered to be a weak molecular interaction?
a. a covalent bond
b. a van der Waals interaction
c. an ionic bond in the presence of water
d. a hydrogen bond
e. A and B only
____ 7. Which one of the atoms shown would be most likely to form an anion with a charge of -1?
a.
d.
b.
c.
____ 8. In a single molecule of water, two hydrogen atoms are bonded to a single oxygen atom by
a. hydrogen bonds.
b. nonpolar covalent bonds.
c. polar covalent bonds.
d. ionic bonds.
e. van der Waals interactions.
e.

____ 9. The slight negative charge at one end of one water molecule is attracted to the slight positive charge of another water
molecule. What is this attraction called?
a. a covalent bond
b. a hydrogen bond
c. an ionic bond
d. a hydrophilic bond
e. a hydrophobic bond
____ 10. Water's high specific heat is mainly a consequence of the
a. small size of the water molecules.
b. high specific heat of oxygen and hydrogen atoms.
c. absorption and release of heat when hydrogen bonds break and form.
d. fact that water is a poor heat conductor.
e. inability of water to dissipate heat into dry air.
____ 11. Hydrophobic substances such as vegetable oil are
a. nonpolar substances that repel water molecules.
b. nonpolar substances that have an attraction for water molecules.
c. polar substances that repel water molecules.
d. polar substances that have an affinity for water.
e. charged molecules that hydrogen-bond with water molecules.
____ 12. Identical heat lamps are arranged to shine on identical containers of water and methanol (wood alcohol), so that each
liquid absorbs the same amount of energy minute by minute. The covalent bonds of methanol molecules are non-polar,
so there are no hydrogen bonds among methanol molecules. Which of the following graphs correctly describes what will
happen to the temperature of the water and the methanol?
a.
d.
b.
c.
e.

____ 13. One of the buffers that contribute to pH stability in human blood is carbonic acid ( ). Carbonic acid is a weak acid
that dissociates into a bicarbonate ion ( ) and a hydrogen ion (H ). Thus,
If the pH of the blood drops, one would expect
a. a decrease in the concentration of and an increase in the concentration of .
b. the concentration of hydroxide ion (OH ) to increase.
c. the concentration of bicarbonate ion ( ) to increase.
d. the to act as a base and remove excess H+ with the formation of .
e. the to act as an acid and remove excess H+ with the formation of .
____ 14. How many electron pairs does carbon share in order to complete its valence shell?
a. 1
b. 2
c. 3
d. 4
e. 8
____ 15. A carbon atom is most likely to form what kind of bond(s) with other atoms?
a. ionic
b. hydrogen
c. covalent
d. A and B only
e. A, B, and C
____ 16. Shown in the figure above are the structures of glucose and fructose. These two molecules differ in the
a. number of carbon, hydrogen, and oxygen atoms
b. types of carbon, hydrogen, and oxygen atoms.
c. arrangement of carbon, hydrogen, and oxygen atoms.
d. number of oxygen atoms joined to carbon atoms by double covalent bonds.
e. answers A, B, and C
Figure 4.5
____ 17. Which of the structures contain(s) a carboxyl functional group? (Refer to the structures shown in Figure 4.5)
a. A
b. B
c. C
d. C and E
e. none of the structures

____ 18. Which of the following is not a polymer? (Refer to the structures shown in Figure 4.5)
a. glucose
b. starch
c. cellulose
d. chitin
e. DNA
____ 19. How many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers long?
a. 12
b. 11
c. 10
d. 9
e. 8
____ 20. Humans can digest starch but not cellulose because
a. the monomer of starch is glucose, while the monomer of cellulose is galactose.
b. humans have enzymes that can hydrolyze the beta (β) glycosidic linkages of starch but not the
alpha (α) glycosidic linkages of cellulose.
c. humans have enzymes that can hydrolyze the alpha (α) glycosidic linkages of starch but not the
beta (β) glycosidic linkages of cellulose.
d. humans harbor starch-digesting bacteria in the digestive tract.
e. the monomer of starch is glucose, while the monomer of cellulose is maltose.
____ 21. What maintains the secondary structure of a protein?
a. peptide bonds
b. hydrogen bonds
c. disulfide bonds
d. ionic bonds
e. phosphodiester bonds
Figure 5.7
____ 22. Figure 5.7 best illustrates the
a. secondary structure of a polypeptide.
b. tertiary structure of a polypeptide.
c. quaternary structure of a protein.
d. double helix structure of DNA.
e. primary structure of a polysaccharide.
____ 23. At which level of protein structure are interactions between the side chains (R groups) most important?
a. primary
b. secondary
c. tertiary
d. quaternary
e. all of the above

____ 24. Which of the following statements about the 5' end of a polynucleotide strand of DNA is correct?
a. The 5' end has a hydroxyl group attached to the number 5 carbon of ribose.
b. The 5' end has a phosphate group attached to the number 5 carbon of ribose.
c. The 5' end has thymine attached to the number 5 carbon of ribose.
d. The 5' end has a carboxyl group attached to the number 5 carbon of ribose.
e. The 5' end is the fifth position on one of the nitrogenous bases.
The following questions are based on the 15 molecules illustrated in Figure 5.8. Each molecule may be used once, more
than once, or not at all.
____ 25. Which molecule is a saturated fatty acid?
a. 1
b. 5
c. 6
d. 8
e. 9
Figure 5.8
____ 26. Which of the following molecules could be joined together by a peptide bond as a result of a dehydration reaction?
a. 2 and 3
b. 3 and 7
c. 7 and 8
d. 8 and 9
e. 12 and 13

____ 27. Which of the following molecules consists of a hydrophilic "head" region and a hydrophobic "tail" region?
a. 2
b. 5
c. 7
d. 9
e. 11
____ 28. Which of the following statements is false?
a. 1 and 4 could be joined together by a glycosidic linkage to form a disaccharide.
b. 9 and 10 could be joined together by ester bonds to form a triacylglycerol.
c. 2 and 7 could be joined together to form a short peptide.
d. 2, 7, and 8 could be joined together to form a short peptide.
e. 14 and 15 could be joined together to form a polypeptide.
29. Construct a table that organizes the following terms, and label the columns and rows.
phosphodiester linkages polypeptides monosaccharides
peptide bonds triacylglycerols nucleotides
glycosidic linkages polynucleotides amino acids
ester linkages polysaccharides fatty acids
Types of biological molecules monomers or components polymers or larger molecule type of linkage
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
B D C D B A D C B C A B D D C C E A C C B A C B E C B E