Question 1

Which of the following correctly describes the structure of a DNA nucleotide as shown in the diagram?

Accepted Answer

A phosphate group, a deoxyribose sugar, and a nitrogenous base

Question 2

During DNA replication, which enzyme is responsible for unwinding the double helix and breaking hydrogen bonds between base pairs?

Accepted Answer

Helicase

Question 3

What type of bond holds the nucleotides together within a single strand of DNA?

Accepted Answer

Phosphodiester bond

Question 4

If the sequence of the template DNA strand is 5' ATGCCTGA 3', what would be the complementary RNA sequence produced during transcription?

Accepted Answer

5' UACGGACU 3'

Question 5

Why are multiple replication bubbles formed during DNA replication in eukaryotic cells?

Accepted Answer

To speed up the replication process by allowing simultaneous copying of different regions

Question 6

Which of the following is NOT a difference between DNA and RNA?

Accepted Answer

DNA contains uracil, while RNA contains thymine

Question 7

What is the directionality of DNA synthesis by DNA polymerase III?

Accepted Answer

5' to 3'

Question 8

Which enzyme replaces RNA primers with DNA nucleotides during DNA replication?

Accepted Answer

DNA polymerase I

Question 9

In the process of translation, what is the function of the anticodon on tRNA?

Accepted Answer

It binds to the mRNA codon to ensure correct amino acid placement

Question 10

Given the mRNA sequence 5' AUG UGU GAG AUA CAU UGG CCA AGA CAC UGU UAG 3', what is the corresponding amino acid sequence?

Accepted Answer

Met-Cys-Glu-Ile-His-Trp-Pro-Arg-His-Cys-Stop

Question 11

Which codon functions as the start signal for translation initiation?

Accepted Answer

AUG

Question 12

What happens when a stop codon enters the A site of the ribosome during translation?

Accepted Answer

A release factor binds, causing the polypeptide chain to be released

Question 13

How many possible triplet codes (codons) can be generated from four RNA bases?

Accepted Answer

$$4^3 = 64$

Question 14

If a mutation changes a DNA base from adenine to guanine, which type of mutation is this?

Accepted Answer

Transition mutation

Question 15

Which of the following best describes the relationship between the N-terminus and C-terminus of a polypeptide chain?

Accepted Answer

The N-terminus is the end with a free amine group, and the C-terminus is the end with a free carboxyl group

Question 16

Which of the following is a real-world consequence of errors in DNA replication?

Accepted Answer

Production of nonfunctional proteins leading to genetic diseases

Question 17

What is the role of single-strand binding proteins during DNA replication?

Accepted Answer

They prevent the renaturation of single-stranded DNA

Question 18

Which of the following statements about Okazaki fragments is correct?

Accepted Answer

They are synthesized discontinuously on the lagging strand

Question 19

Which bond is formed by ligase during DNA replication?

Accepted Answer

Phosphodiester bond

Flow of Genetic Information: DNA Replication, Transcription, and Translation

Study Guide - Practice Questions