Question 1

Which scientist used X-ray diffraction to capture Photo 51, which was crucial in determining the structure of DNA?

Accepted Answer

Rosalind Franklin

Question 2

What is the correct base pairing in DNA according to Watson and Crick's model?

Accepted Answer

Adenine pairs with thymine, guanine pairs with cytosine

Question 3

In the DNA double helix, the two strands run in opposite directions. What is this arrangement called?

Accepted Answer

Antiparallel

Question 4

During DNA polymerization, a phosphodiester bond is formed between a phosphate group and which group on the adjacent nucleotide?

Accepted Answer

The 3' OH group

Question 5

What is the significance of complementary base pairing in the DNA double helix?

Accepted Answer

It permits complementary base pairing, ensuring accurate replication.

Question 6

Which enzyme is responsible for unwinding the DNA double helix at the replication fork?

Accepted Answer

Helicase

Question 7

What is the primary function of single-stranded binding proteins (SSBs) during DNA replication?

Accepted Answer

They prevent reannealing and degradation of separated DNA strands.

Question 8

In prokaryotic DNA replication, where does replication begin?

Accepted Answer

At a single origin of replication (ORI)

Question 9

Which of the following statements about DNA replication forks is INCORRECT?

Question 10

What is the function of topoisomerase (DNA gyrase) during DNA replication?

Accepted Answer

It relieves DNA supercoiling ahead of the replication fork.

Question 11

According to the central dogma of molecular biology, what is the intermediate molecule between DNA and protein?

Accepted Answer

mRNA

Question 12

Which process is responsible for converting the genetic information in DNA into a functional protein?

Accepted Answer

Translation

Question 13

Which enzyme synthesizes new DNA strands using an existing DNA strand as a template?

Accepted Answer

DNA polymerase

Question 14

What is the role of RNA primers during DNA replication?

Accepted Answer

They provide a starting point for DNA synthesis.

Question 15

Which of the following best describes the flow of genetic information according to the central dogma?

Accepted Answer

DNA → RNA → Protein

Question 16

Which of the following is a real-world application of understanding DNA replication mechanisms?

Accepted Answer

Designing antibiotics that target bacterial DNA gyrase

Question 17

If a mutation occurs in the gene encoding helicase, what is the most likely consequence for DNA replication?

Accepted Answer

The DNA double helix will not be unwound, halting replication.

Question 18

Which of the following statements about eukaryotic DNA replication origins is correct?

Accepted Answer

Eukaryotic chromosomes have multiple origins of replication.

Question 19

Which process is responsible for the synthesis of RNA from a DNA template?

Accepted Answer

Transcription

Question 20

What is the full process by which genotype becomes expressed as phenotype called?

Accepted Answer

Gene expression

DNA Structure, Replication, and the Central Dogma of Molecular Biology

Study Guide - Practice Questions