Question 1

Given the following strand of DNA: 5′ CATAGCCTTA 3′
Which of the following sequences is the complementary DNA strand?

Accepted Answer

A) 5′ CATAGCCTTA 3′ 
B) 3′ GTATCGGAAT 5′ 
C) 5′ GTATCGGAAT 3′ 
D) 3′ GUAUCGGAAU 5′ 
E) 3′ CATAGCCTTA 5′

Question 2

Which type of virus causes polio and AIDS?

Accepted Answer

A) retrovirus 
B) reovirus 
C) bacteriophage 
D) adenovirus 
E) parvovirus

Question 3

The nucleotide that is present in RNA but not DNA is

Accepted Answer

A) thymine. 
B) uracil. 
C) adenine. 
D) cytosine. 
E) guanine.

Question 4

With respect to DNA structure, polarity means that

Accepted Answer

A) DNA nucleotides can be either positively or negatively charged. 
B) the phosphate backbone of DNA is negatively charged. 
C) DNA nucleotides can be charged or uncharged. 
D) DNA strands have a 5′ direction and a 3′ direction.

Question 5

What is the correct order of these events in recombination that is resolved by the crossover pathway? 1.Double-strand break formation
2.Strand invasion
3.Resection
4.Resolution of the double Holliday junction
5.Branch migration
6.Formation of a double Holliday junction

Accepted Answer

A) 6, 1, 2, 5, 3, 4 
B) 1, 2, 5, 3, 6, 4 
C) 6, 4, 1, 2, 5, 3 
D) 1, 3, 2, 6, 5, 4 
E) 1, 2, 3, 5, 6, 4

Question 6

Eukaryotic chromosomes have evolved ________ at the ends of linear chromosomes to ensure the replication of the two ends of the chromosomes.

Accepted Answer

A) methylases 
B) capping proteins 
C) ligases 
D) telomeres 
E) single-stranded binding proteins

Question 7

Which protein is needed to lay down a segment of RNA complementary to the DNA before replication can begin?

Accepted Answer

A) RNA polymerase II 
B) primase 
C) helicase 
D) topoisomerase 
E) ligase

Question 8

A chromosome of genotype C D recombines with a homolog of genotype c d during meiosis when Spo11 produces a double-strand break between the two loci.If anticrossover helicase disentangles the invading strand, the likely outcome would be

Accepted Answer

A) two C D and two c d gametes. 
B) two C d and two c D gametes. 
C) one C D, one C d, one c D, and one c d gamete. 
D) four C D gametes. 
E) four c d gametes

Question 9

Which term is used to describe the overall 5′-to-3′ direction of linked nucleotides in a DNA chain?

Accepted Answer

A) complementarity 
B) sequence 
C) polarity 
D) primacy

Question 10

Hershey and Chase relied on ________ to physically separate the infected bacterial cells from the phage ghosts.

Accepted Answer

A) radioactivity 
B) gel filtration 
C) ion exchange 
D) centrifugation

Question 11

In the Hershey and Chase experiment designed to determine the molecule of heredity, what was radiolabeled with 35S?

Accepted Answer

A) protein 
B) DNA 
C) RNA 
D) rRNA

Question 12

X-ray data showed that the spacing between repeating units along the axis of the DNA helix is

Accepted Answer

A) 2.0 angstroms. 
B) 3.4 angstroms. 
C) 20 angstroms. 
D) 34 angstroms.

Question 13

Which protein relaxes supercoils by nicking the DNA?

Accepted Answer

A) topoisomerase 
B) helicase 
C) primase 
D) ligase 
E) telomerase

Exam 6: DNA Structure, Replication, and Recombination

Given the following strand of DNA: 5′ CATAGCCTTA 3′ Which of the following sequences is the complementary DNA strand?