Chapter 1: DNA

Multiple Choice
Identify the choice that best completes the statement or answers the question.

____	1.	DNA contains deoxyribonucleotide triphosphates joined together by what type of covalent bond?
a.	Aldehyde	
b.	Ester	
c.	Phosphodiester	
d.	Peptide	

____	2.	Nucleotides in DNA consist of which of the following?
a.	Nitrogen base, deoxyribose, and phosphate	
b.	Nitrogen base, ribose, and sulfur	
c.	Carbon base, ribose, and phosphate	
d.	Carbon base, glucose, and carboxyl	

____	3.	Which of the five ribose carbons of the deoxyribonucleotide are involved in formation of the DNA chain?
a.	1’ and 5’	
b.	2’ and 4’	
c.	3’ and 4’	
d.	3’ and 5’	

____	4.	In a DNA molecule, one end has a free hydroxyl group and one end has a free ___________.
a.	phosphate group	
b.	hydroxyl group	
c.	amino group	
d.	carboxyl group	

____	5.	What type of bonds spontaneously form between two complementary strands of DNA?
a.	Hydrogen bonds	
b.	Covalent bonds	
c.	Phosphodiester bonds	
d.	Polar covalent bonds	

____	6.	In a double-stranded DNA molecule, base pairing between strands occurs between:
a.	A purine and a purine	
b.	A pyrimidine and a pyrimidine	
c.	A purine and a pyrimidine	
d.	Any type of nucleotide base	

____	7.	Which of the following is a purine?
a.	Thymine	
b.	Cytosine	
c.	Adenine	
d.	Alanine	

____	8.	Which DNA sequence is complementary to 5¢GATTCTCAAAGGACT3¢?
a.	5¢GATTCTCAAAGGACT3¢	
b.	3¢GATTCTCAAAGGACT5¢	
c.	3¢CTAAGAGTTTCCTGA5¢	
d.	5¢CTAAGAGTTTCCTGA3¢	

____	9.	The term used to describe the arrangement of the individual strands in the double-stranded DNA molecule is:
a.	Parallel	
b.	Antiparallel	
c.	Tangential	
d.	Divergent	

____	10.	The process of separating the two DNA strands into two single strands is called:
a.	Denaturation	
b.	Bidirectional	
c.	Depolymerization	
d.	Synthesis	

____	11.	DNA replication is:
a.	Conservative	
b.	Semiconservative	
c.	Nonconservative	
d.	Dispersive	

____	12.	DNA replication requires the presence of:
a.	DNA template	
b.	Pyrophosphate	
c.	Amino acids	
d.	Messenger RNA	

____	13.	DNA replication proceeds with the new daughter strand synthesized in the following orientation:
a.	5¢to 3¢	
b.	3¢to 5¢	
c.	The daughter strand is not synthesized in any order.	
d.	Either 5¢to 3¢or 3¢ to 5¢	

____	14.	In DNA replication, the leading strand is the strand that has which orientation?
a.	5¢to 3¢	
b.	3¢to 5¢	
c.	Both strands are leading.	

____	15.	The lagging DNA strand is synthesized discontinuously producing:
a.	Kornberg fragments	
b.	Southern fragments	
c.	Okazaki fragments	
d.	Klenow fragments	

____	16.	Which of the following does not play a role in DNA replication?
a.	RNA primer	
b.	Deoxynucleotide	
c.	Stop codon	
d.	DNA polymerase	

____	17.	In DNA replication, where does replication begin and end?
a.	Origin of replication; end of the molecule	
b.	Promoter; termination site	
c.	Start codon; stop codon	
d.	Start codon, termination site	

____	18.	Which of the following enzymes will untangle DNA?
a.	Polymerase	
b.	Helicase	
c.	Kinase	
d.	Phosphatase	

____	19.	Restriction endonucleases are enzymes that are produced by bacteria and __________.
a.	degrade viral proteins	
b.	digest DNA	
c.	have no laboratory applications	
d.	degrade lipids	

____	20.	Enzymes that recognize palindromic sequences of DNA, that are cut within the recognition sequence, that do not have methylating activity, and that are used frequently in the laboratory are which type of restriction enzymes?
a.	Type I	
b.	Type II	
c.	Type III	
d.	Type IV	

____	21.	Which of the following is a type II restriction enzyme recognition site?
a.	GAATTC	
b.	GAATTG	
c.	GAAAAG	
d.	GATCAG	

____	22.	An exonuclease will catalyze what type of reaction?
a.	Polymerization of nucleotides into long strands	
b.	Separation of complementary DNA strands	
c.	Dissociation of phosphodiester bonds at the ends of DNA molecules	
d.	Formation of circular DNA molecules from linear ones	

____	23.	What reactions are catalyzed by DNA methyltransferase?
a.	Addition of methyl groups to nitrogen bases	
b.	Addition of methyl groups to ribose sugars	
c.	Addition of methyl groups to proteins	
d.	Removal of methyl groups from DNA	

____	24.	The purpose of ligase is to:
a.	Synthesize DNA	
b.	Cut DNA within the double helix	
c.	Chew DNA from the ends	
d.	Paste two ends of DNA together	

____	25.	What is the fertility factor (F) observed by Hayes and Lederberg?
a.	A chemical that encourages bacterial mating	
b.	A virus	
c.	A plasmid	
d.	A polysaccharide on the cell surface	

____	26.	Avery, MacLeod, and McCarty identified the nature of Griffith’s transforming factor in an experiment where it was destroyed by what treatment?
a.	Protease	
b.	Ribonuclease	
c.	Deoxyribonuclease	
d.	Heating	

____	27.	The movement of DNA from one bacterium to another through the activity of bacteriophages is called:
a.	Conjugation	
b.	Transformation	
c.	Transduction	
d.	Crossing over	

____	28.	In sexual recombination, new combinations of genes are created by which of the following processes?
a.	Transduction	
b.	Crossing over	
c.	Conjugation	
d.	Transformation	

____	29.	Which of the following promote resistance to common antibiotics?
a.	Helicases	
b.	R factors	
c.	Endonucleases	
d.	Methylases	

____	30.	Recombination between a plasmid and the cell chromosome will result in:
a.	Rapid degradation of the chromosome	
b.	Death of the cell	
c.	Immediate cellular replication	
d.	Stable integration of plasmid genes into the chromosome	

Chapter 1: DNA
Answer Section

MULTIPLE CHOICE

	1.	ANS:	C	PTS:	1

	2.	ANS:	A	PTS:	1

	3.	ANS:	D	PTS:	1

	4.	ANS:	A	PTS:	1

	5.	ANS:	A	PTS:	1

	6.	ANS:	C	PTS:	1

	7.	ANS:	C	PTS:	1

	8.	ANS:	C	PTS:	1

	9.	ANS:	B	PTS:	1

	10.	ANS:	A	PTS:	1

	11.	ANS:	B	PTS:	1

	12.	ANS:	A	PTS:	1

	13.	ANS:	A	PTS:	1

	14.	ANS:	B	PTS:	1

	15.	ANS:	C	PTS:	1

	16.	ANS:	C	PTS:	1

	17.	ANS:	A	PTS:	1

	18.	ANS:	B	PTS:	1

	19.	ANS:	B	PTS:	1

	20.	ANS:	B	PTS:	1

	21.	ANS:	A	PTS:	1

	22.	ANS:	C	PTS:	1

	23.	ANS:	A	PTS:	1

	24.	ANS:	D	PTS:	1

	25.	ANS:	C	PTS:	1

	26.	ANS:	C	PTS:	1

	27.	ANS:	C	PTS:	1

	28.	ANS:	B	PTS:	1

	29.	ANS:	B	PTS:	1

	30.	ANS:	D	PTS:	1