Question 1

Which feature distinguishes eukaryotic DNA replication from bacterial DNA replication?

Accepted Answer

Eukaryotic chromosomes contain multiple origins of replication (ORIs), while bacterial chromosomes typically have a single ORI.

Question 2

What is the primary function of telomeres in eukaryotic chromosomes?

Accepted Answer

To preserve the integrity and stability of chromosome ends by preventing degradation and fusion.

Question 3

In yeast, what is the significance of autonomously replicating sequences (ARSs)?

Accepted Answer

They function as origins of replication, allowing DNA synthesis to begin.

Question 4

Which DNA polymerase is responsible for synthesizing the leading strand during eukaryotic DNA replication?

Accepted Answer

Pol ε

Question 5

What is the role of chromatin assembly factors (CAFs) during DNA replication?

Accepted Answer

They facilitate the assembly of nucleosomes onto newly synthesized daughter strands.

Question 6

Why do eukaryotic chromosomes require telomerase for complete replication?

Accepted Answer

Because the ends of linear chromosomes cannot be fully replicated by standard DNA polymerases, leading to progressive shortening.

Question 7

Which component of telomerase acts as a template for the addition of telomeric repeats?

Accepted Answer

TERC (telomerase RNA component)

Question 8

A cell line is observed to have short telomeres and lacks telomerase activity. What is the most likely consequence for these cells?

Accepted Answer

They will enter senescence and cease cell division.

Question 9

Which equation best represents the directionality of DNA synthesis by DNA polymerases?

Accepted Answer

DNA synthesis proceeds in the $$5' \rightarrow 3'$$ direction.

Question 10

In Tetrahymena, the telomerase RNA component contains the sequence $$3'	ext{CCCCAA}5'. $$What sequence will telomerase generate on the telomere?

Accepted Answer

$$5'	ext{GGGGTT}3'$$

Question 11

Which process occurs after the RNA primer is synthesized during eukaryotic DNA replication?

Accepted Answer

Pol δ and Pol ε replace Pol α for elongation of the lagging and leading strands, respectively.

Question 12

What is the consequence of nucleases acting on unprotected chromosome ends?

Accepted Answer

They degrade the DNA, leading to loss of genetic material.

Question 13

Which of the following best describes the function of the shelterin complex?

Accepted Answer

It protects telomeres from being recognized as double-stranded breaks.

Question 14

A mutation in the TERT gene would most likely affect which cellular process?

Accepted Answer

Addition of telomeric repeats to chromosome ends.

Question 15

Which equation represents the number of nucleosomes per 200 base pairs of DNA?

Accepted Answer

There are $$1$$ nucleosome per $$200$$ base pairs.

Question 16

Which of the following is a plausible outcome if telomerase is overexpressed in somatic cells?

Accepted Answer

Cells may acquire unlimited replicative potential, increasing cancer risk.

Question 17

During DNA replication, what is the fate of nucleosomes?

Accepted Answer

They are stripped away before polymerase can begin synthesis and reassembled onto daughter strands.

Question 18

Which step is necessary for the synthesis of Okazaki fragments on the lagging strand?

Accepted Answer

RNA primer synthesis by Pol α.

Question 19

Which equation describes the relationship between the number of origins of replication and the speed of DNA synthesis in eukaryotes?

Accepted Answer

Speed of DNA synthesis increases as the number of origins increases.

Question 20

Which of the following is a key difference between prokaryotic and eukaryotic DNA replication?

Accepted Answer

Eukaryotic DNA replication involves chromatin remodeling.

Ch 10 P2 Eukaryotic DNA Replication and Telomere Maintenance

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