Question 1

Which molecular technique is most suitable for detecting microdeletions that are too small to be visualized by chromosome banding patterns?

Accepted Answer

Fluorescent in situ hybridization (FISH)

Question 2

A chromosome inversion in which the centromere is outside the inverted region is called:

Accepted Answer

Paracentric inversion

Question 3

What is the genetic consequence of crossing over within a paracentric inversion?

Accepted Answer

Formation of a dicentric chromosome and an acentric fragment

Question 4

Which type of translocation involves the fusion of two nonhomologous chromosomes?

Accepted Answer

Robertsonian translocation

Question 5

The Philadelphia chromosome, associated with chronic myelogenous leukemia (CML), is the result of which genetic event?

Accepted Answer

A reciprocal translocation between chromosomes 9 and 22

Question 6

Which statement best describes a silent mutation?

Accepted Answer

A base-pair change that does not alter the amino acid sequence

Question 7

A transition mutation is defined as:

Accepted Answer

A purine replaces another purine, or a pyrimidine replaces another pyrimidine

Question 8

Why are dominant mutations generally easier to study than recessive mutations?

Accepted Answer

Dominant mutations manifest in the phenotype even in heterozygotes

Question 9

Which of the following is a plausible reason for a gene to be a mutational hotspot?

Accepted Answer

It has a large gene size

Question 10

What is the main advantage of whole genome sequencing in mutation rate determination?

Accepted Answer

It enables assessment of mutation rates throughout the entire genome

Question 11

A missense mutation in a protein-coding gene results in:

Accepted Answer

A change in the amino acid sequence of the protein

Question 12

Which of the following best describes a base-pair substitution mutation?

Accepted Answer

The replacement of one nucleotide base pair by another

Question 13

In the context of chromosome pairing and recombination, what is the result of alignment between a normal chromosome and its inverted homolog?

Accepted Answer

Formation of an inversion loop at synapsis

Question 14

Which type of mutation provides raw material for evolutionary changes?

Accepted Answer

Mutations that occur at random in every generation

Question 15

Which of the following is true about reciprocal balanced translocations?

Accepted Answer

They occur when pieces of two nonhomologous chromosomes switch places

Question 16

A nonsense mutation in a gene will most likely result in:

Accepted Answer

A truncated protein due to a premature stop codon

Question 17

Which of the following is a consequence of crossing over within the inverted region of a chromosome?

Accepted Answer

Duplications and deletions in the recombinant chromosomes

Question 18

Which of the following statements about mutation frequency is correct?

Accepted Answer

Mutation frequencies vary among genes of a single species

Question 19

Which of the following is NOT a type of base-pair substitution mutation?

Accepted Answer

Frameshift mutation

Question 20

In a FISH experiment, what would be the expected result if a microduplication occurred at the region targeted by probe B?

Accepted Answer

Two fluorescent spots from probe B

DNA Mutation and Repair: Mechanisms, Types, and Detection

Study Guide - Practice Questions