Question 1

Which level of protein structure is directly determined by the sequence of amino acids encoded by a gene?

Accepted Answer

Primary structure

Question 2

A mutation changes a codon from UAU (tyrosine) to UAA (stop codon). What type of mutation is this?

Accepted Answer

Nonsense mutation

Question 3

Which of the following best describes the role of R-groups in amino acids?

Accepted Answer

They determine the chemical identity and properties of each amino acid.

Question 4

In the Beadle and Tatum experiment with Neurospora, what did the inability of a mutant strain to grow on minimal medium indicate?

Accepted Answer

The strain lacked the ability to synthesize a specific compound required for growth.

Question 5

Which of the following mutations is most likely to be inherited by offspring?

Accepted Answer

X-linked mutation in sperm

Question 6

A frameshift mutation occurs when:

Accepted Answer

A nucleotide is inserted or deleted, altering the reading frame of the gene.

Question 7

Which process links amino acids together in a protein?

Accepted Answer

Peptide bond formation

Question 8

What is the effect of a silent mutation on the protein product?

Accepted Answer

No change in the amino acid sequence

Question 9

Which of the following is an example of a transition mutation?

Accepted Answer

Adenine replaced by guanine

Question 10

A patient with phenylketonuria (PKU) cannot metabolize phenylalanine due to a mutation in which type of gene?

Accepted Answer

Enzyme-coding gene

Question 11

Which level of protein structure involves the association of multiple polypeptide subunits?

Accepted Answer

Quaternary structure

Question 12

If a mutation causes the loss of a base during DNA replication, what is this process called?

Accepted Answer

Depurination

Question 13

Which of the following best explains why genetic spores are advantageous for genetic studies?

Accepted Answer

They are haploid, so mutations are directly expressed.

Question 14

Which of the following is a consequence of a tautomeric shift during DNA replication?

Accepted Answer

Anomalous base pairing leading to spontaneous mutation

Question 15

A mutation changes the codon AAA (lysine) to AGA (arginine). What type of mutation is this?

Accepted Answer

Missense mutation

Question 16

Which of the following best describes the 'one gene, one enzyme' hypothesis?

Accepted Answer

Each gene encodes a single enzyme that affects a specific biochemical pathway.

Question 17

Which of the following is a real-world example of a mutation caused by deamination?

Accepted Answer

Conversion of cytosine to uracil

Question 18

A mold strain cannot grow on minimal medium but grows when supplemented with arginine. What does this indicate?

Accepted Answer

The strain is auxotrophic for arginine.

Question 19

Which of the following best describes a synonymous mutation?

Accepted Answer

A nucleotide change that does not alter the amino acid sequence

Question 20

Which of the following is a spontaneous mutation mechanism?

Accepted Answer

Replication errors such as slippage in repeat regions

Protein Structure, Gene Function, and Mutations in Genetics

Study Guide - Practice Questions