Question 1

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

Accepted Answer

A five-carbon sugar (deoxyribose), a phosphate group, and a nitrogenous base (thymine)

Question 2

During DNA replication, which enzyme is responsible for joining Okazaki fragments on the lagging strand?

Accepted Answer

DNA ligase

Question 3

Which statement best explains why DNA replication is described as 'semi-conservative'?

Accepted Answer

Each new DNA molecule contains one original strand and one new strand

Question 4

If a DNA molecule has 30% adenine, what percentage of guanine would you expect to find?

Accepted Answer

$$20\%$$

Question 5

Which of the following is a purine base found in DNA?

Accepted Answer

Adenine

Question 6

What is the role of messenger RNA (mRNA) in protein synthesis?

Accepted Answer

It carries the genetic code from DNA to the ribosome for translation

Question 7

Which process occurs in the nucleus and involves the synthesis of RNA from a DNA template?

Accepted Answer

Transcription

Question 8

A mutation that changes a codon from UAU (tyrosine) to UAA (stop codon) will most likely result in:

Accepted Answer

A truncated, non-functional protein

Question 9

Which of the following modifications occurs to eukaryotic mRNA before it is exported from the nucleus?

Accepted Answer

Addition of a 5' cap and a poly-A tail

Question 10

What is the function of transfer RNA (tRNA) during translation?

Accepted Answer

It carries amino acids to the ribosome and matches them to the codons in mRNA

Question 11

Which of the following codons signals the start of translation and encodes methionine?

Accepted Answer

$$AUG$$

Question 12

A base insertion mutation in a gene is likely to cause:

Accepted Answer

A frameshift mutation

Question 13

Which statement best describes the Central Dogma of Biology?

Accepted Answer

DNA is transcribed to RNA, which is then translated to protein

Question 14

Which of the following is true about the directionality of DNA strands?

Accepted Answer

The two strands run in opposite directions (antiparallel)

Question 15

Which of the following is a consequence of a base substitution mutation that changes a codon to a stop codon?

Accepted Answer

The protein will be truncated and likely non-functional

Question 16

Which enzyme is responsible for synthesizing RNA during transcription?

Accepted Answer

RNA polymerase

Question 17

What is the function of ribosomes in the cell?

Accepted Answer

They build proteins from mRNA templates

Question 18

Which of the following statements about prokaryotic and eukaryotic ribosomes is correct?

Accepted Answer

Eukaryotic ribosomes are larger and made from different components than prokaryotic ribosomes

Question 19

Which of the following best describes a codon?

Accepted Answer

A sequence of three nucleotides in mRNA that encodes a specific amino acid

Question 20

Which of the following is a likely result of a mutation caused by UV light?

Accepted Answer

A mutation induced by a physical mutagen

Molecular Genetics: Structure, Function, and Expression of Genetic Material

Study Guide - Practice Questions