1.	Which of the following enzymes will untangle DNA?
A)	Polymerase
B)	Helicase
C)	Kinase
D)	Phosphatase

2.	Which DNA sequence is homologous to 5¢GATTCTCAAAGGACT3¢?
A)	5¢GATTCTCAAAGGACT3¢
B)	3¢GATTCTCAAAGGACT5¢
C)	3¢CTAAGAGTTTCCTGA5¢
D)	5¢CTAAGAGTTTCCTGA3¢

3.	Restriction endonucleases are enzymes that are produced by bacteria and __________
A)	degrade viral proteins
B)	degrade DNA
C)	have no laboratory applications
D)	degrade lipids

4.	In a DNA molecule, the 5¢ end contains a free ___________
A)	phosphate group
B)	hydroxyl group
C)	amino group
D)	carboxyl group

5.	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)	none of the above

6.	One DNA strand binds to the other strand through:
A)	peptide bonds
B)	disulfide bonds
C)	hydrogen bonds
D)	phosphodiester bonds

7.	DNA replication is:
A)	conservative
B)	semiconservative
C)	nonconservative
D)	dispersive

8.	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

9.	DNA replication requires the presence of:
A)	DNA template
B)	RNA polymerase
C)	amino acids
D)	messenger RNA

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 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¢

12.	The lagging DNA strand is synthesized discontinuously producing:
A)	Kornberg fragments
B)	Southern fragments
C)	Okasaki fragments
D)	Klenow fragments

13.	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)	None of the above

14.	An exon is:
A)	spliced out
B)	an open reading frame (ORF)
C)	a DNA-binding protein
D)	within 100 bp of ORFs

15.	The nucleotides in a single strand of DNA are held together by which of the following bonds?
A)	Disulfide
B)	Phosphodiester
C)	Hydrogen
D)	Peptide

16.	In DNA replication, the leading strand is the strand that has which conformation?
A)	5¢ to 3¢
B)	3¢ to 5¢
C)	Both strands are leading

17.	Which of the following is a purine?
A)	Thymine
B)	Cytosine
C)	Adenine
D)	Alanine

18.	Which of the following does not play a role in DNA replication?
A)	RNA primer
B)	Deoxynucleotide
C)	Stop codon
D)	DNA polymerase

19.	The purpose of endonucleases 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

20.	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

21.	Adenine, thymine, guanine, and cytosine are what components of DNA?
A)	Hydrogen bonds
B)	Sugar moieties
C)	Phosphodiester groups
D)	Nitrogen bases

22.	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

23.	In sexual recombination, new combinations of genes are created by which of the following processes?
A)	Transduction
B)	Crossing over
C)	Conjugation
D)	Transformation

24.	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

Answer Key

1.	B
2.	C
3.	B
4.	A
5.	B
6.	C
7.	B
8.	C
9.	A
10.	A
11.	A
12.	C
13.	A
14.	B
15.	B
16.	B
17.	C
18.	C
19.	B
20.	A
21.	D
22.	C
23.	B
24.	B