Question 1

Which of the following correctly describes the structure of a DNA nucleotide?

Accepted Answer

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

Question 2

Which nitrogenous base is found in RNA but not in DNA?

Accepted Answer

Uracil

Question 3

What type of bond holds the two strands of DNA together?

Accepted Answer

Hydrogen bonds

Question 4

During DNA replication, which enzyme is primarily responsible for synthesizing the new DNA strand?

Accepted Answer

DNA polymerase

Question 5

Which of the following best describes the directionality of DNA strands?

Accepted Answer

One strand runs 5' to 3', the other runs 3' to 5'

Question 6

Which process involves copying a section of DNA into a complementary RNA sequence?

Accepted Answer

Transcription

Question 7

In the process of protein synthesis, what is the role of transfer RNA (tRNA)?

Accepted Answer

Brings amino acids to the ribosome during translation

Question 8

Which of the following is the correct sequence of events in gene expression?

Accepted Answer

Transcription → RNA splicing → Translation

Question 9

If a DNA sequence is 5'-ATGCGT-3', what is the complementary RNA sequence produced during transcription?

Accepted Answer

3'-UACGCA-5'

Question 10

Which of the following statements about messenger RNA (mRNA) is TRUE?

Accepted Answer

mRNA is single stranded and carries genetic information to the ribosome

Question 11

During RNA splicing, which regions are removed from the primary RNA transcript?

Accepted Answer

Introns

Question 12

Which of the following is NOT a component of a nucleotide?

Accepted Answer

Amino acid

Question 13

What is the function of ribosomal RNA (rRNA) in protein synthesis?

Accepted Answer

Forms the core of the ribosome and catalyzes peptide bond formation

Question 14

Which base pairing is correct in DNA?

Accepted Answer

Cytosine pairs with Guanine

Question 15

A mutation changes a DNA base from cytosine to thymine. What is the most direct effect this could have on the resulting protein?

Accepted Answer

It could change the amino acid sequence coded by the gene

Question 16

Which equation best represents the base pairing in DNA?

Accepted Answer

$A = T$ and $C = G$

Question 17

If a DNA molecule is 3.4 nm per turn and contains 10 base pairs per turn, what is the distance between adjacent base pairs?

Accepted Answer

$0.34\ \mathrm{nm}$

Question 18

Which step in transcription involves the RNA polymerase binding to the promoter region of DNA?

Accepted Answer

Initiation

Question 19

Which of the following best explains why DNA cannot leave the nucleus but proteins are made in the cytoplasm?

Accepted Answer

DNA is too large and fragile to pass through the nuclear envelope

Question 20

During translation, what is the relationship between codons and amino acids?

Accepted Answer

Each codon in mRNA specifies a particular amino acid

DNA, RNA, and Protein Synthesis: Structure and Function

Study Guide - Practice Questions