$$RF = \frac{\text{Number of recombinant offspring}}{\text{Total number of offspring}} \times 100$$

Question 1

Which of the following best explains why genes located farther apart on the same chromosome have a higher recombination frequency?

Accepted Answer

They are less likely to be inherited together because crossing over is more probable between them.

Question 2

During meiosis, a crossover occurs between a gene and its centromere. Which outcome is most likely regarding allele segregation?

Accepted Answer

The crossover will result in recombinant chromatids, altering the expected segregation pattern.

Question 3

Which experiment provided direct evidence that DNA, not protein, is the genetic material in bacteriophages?

Accepted Answer

Hershey and Chase's experiment using radioactive phosphorus and sulfur

Question 4

Which of the following statements about DNA replication in bacteria is correct?

Accepted Answer

Replication begins at a single origin and proceeds bidirectionally.

Question 5

Which enzyme is responsible for relieving positive supercoiling ahead of the replication fork in bacteria?

Accepted Answer

DNA gyrase

Question 6

A student is asked to distinguish between a nucleotide and a nucleoside. Which feature is unique to a nucleotide?

Accepted Answer

Presence of one or more phosphate groups

Question 7

Which of the following best describes the antiparallel nature of double-stranded DNA?

Accepted Answer

One strand runs 5′ to 3′, while the other runs 3′ to 5′.

Question 8

Which equation correctly represents the calculation of recombination frequency ($$RF) $$between two genes?

Accepted Answer

$$RF = \frac{	ext{Number of recombinant offspring}}{	ext{Total number of offspring}} 	imes 100$$

Question 9

Which RNA class is most abundant in cells and plays a structural and catalytic role in ribosomes?

Accepted Answer

rRNA

Question 10

A scientist uses FISH (fluorescent in situ hybridization) to detect a gene on a chromosome. What is the principle behind this technique?

Accepted Answer

Labeled nucleic acid probes hybridize to specific DNA sequences, allowing visualization.

Question 11

Which of the following statements about telomerase is correct?

Accepted Answer

Telomerase uses an internal RNA template and reverse transcriptase activity to extend telomeres.

Question 12

Which DNA polymerase is primarily responsible for synthesizing the lagging strand in eukaryotic cells?

Accepted Answer

DNA polymerase δ

Question 13

Which of the following best explains the maternal effect in genetics?

Accepted Answer

The mother's nuclear genotype determines the offspring's early phenotype via gene products in the egg.

Question 14

Which feature supports the endosymbiotic origin of mitochondria and chloroplasts?

Accepted Answer

Circular genomes and bacterial-like ribosomes

Question 15

Which equation correctly represents the directionality of DNA synthesis by DNA polymerases?

Accepted Answer

$$	ext{DNA synthesis occurs in the } 5' ightarrow 3' 	ext{ direction}$$

Question 16

Which process is responsible for the discontinuous synthesis of the lagging strand during DNA replication?

Accepted Answer

Formation of Okazaki fragments

Question 17

A patient with a mitochondrial disorder is considering mitochondrial replacement therapy. What is the primary goal of this therapy?

Accepted Answer

To reduce transmission of pathogenic mitochondrial DNA by nuclear transfer

Question 18

Which of the following distinguishes deoxyribose from ribose in nucleic acids?

Accepted Answer

Deoxyribose has an H at the 2′ carbon, while ribose has an OH.

Question 19

Which of the following is a consequence of telomere shortening in most somatic cells?

Accepted Answer

Cellular aging and eventual loss of replicative ability

Genetics Exam Two Study Guide: Linkage, Extranuclear Inheritance, DNA Structure, and Replication

Study Guide - Practice Questions