Question 1

Which of the following best describes the function of a reporter gene in genetic engineering experiments?

Accepted Answer

It allows visualization of gene expression patterns by producing a detectable product.

Question 2

Green Fluorescent Protein (GFP) is commonly used in molecular biology because:

Accepted Answer

It causes cells to glow green under UV light, allowing researchers to track gene expression.

Question 3

In a blue-white screening experiment, what is the expected result if a bacterial colony expresses the lacZ gene?

Accepted Answer

The colony will appear blue due to conversion of X-gal by β-galactosidase.

Question 4

Which of the following is a critical requirement for Cas9 to recognize and cleave a target DNA sequence?

Accepted Answer

Presence of a protospacer adjacent motif (PAM) sequence immediately downstream of the target site.

Question 5

A scientist wants to disrupt a gene in mice using CRISPR-Cas9. After introducing a double-strand break, which DNA repair pathway is most likely to introduce small insertions or deletions at the cut site?

Accepted Answer

Non-Homologous End Joining (NHEJ)

Question 6

Which of the following best explains why most genes analyzed with LacZ reporter constructs are found to be tissue-specific?

Accepted Answer

Gene regulatory regions often contain elements that restrict expression to certain cell types.

Question 7

A researcher is designing a single guide RNA (sgRNA) for CRISPR-Cas9. Which of the following components must be included in the sgRNA?

Accepted Answer

A 20-nucleotide guiding region complementary to the target DNA and a scaffold region for Cas9 binding.

Question 8

Which of the following is a real-world application of CRISPR-Cas9 technology?

Accepted Answer

Engineering mosquitoes to resist malaria parasites.

Question 9

In the context of gene drives, what is the primary mechanism by which a gene drive increases the inheritance of a particular gene in a population?

Accepted Answer

Homology Directed Repair (HDR) copies the gene drive element onto the homologous chromosome after a double-strand break.

Question 10

A transgenic cat expressing GFP is compared to a control cat under UV light. What is the most likely explanation for the observed difference?

Accepted Answer

The transgenic cat has a GFP gene integrated into its genome, causing its tissues to fluoresce green under UV light.

Question 11

Which of the following best describes the role of the PAM sequence in CRISPR-Cas9 genome editing?

Accepted Answer

It is required for Cas9 to bind and cleave the target DNA.

Question 12

A researcher uses CRISPR-Cas9 to introduce a specific point mutation into a gene. Which DNA repair pathway must be active for this precise editing to occur?

Accepted Answer

Homology Directed Repair (HDR)

Question 13

Which of the following statements about the evolution of CRISPR-Cas9 is correct?

Accepted Answer

CRISPR-Cas9 evolved as a bacterial immune system to defend against viral infections.

Question 14

Which of the following is NOT a potential application of CRISPR-Cas9 technology?

Accepted Answer

Measuring protein-protein interactions using FRET.

Question 15

A scientist wants to visualize the expression of a gene in a developing frog embryo. Which reporter gene would be most appropriate for this experiment?

Accepted Answer

GFP (Green Fluorescent Protein)

Question 16

Which of the following best explains why yellow and red versions of fluorescent proteins are useful in genetic experiments?

Accepted Answer

They allow simultaneous investigation of multiple genes by using different colors.

Question 17

In the natural bacterial CRISPR system, what is the function of the crRNA-tracrRNA duplex?

Accepted Answer

It guides the Cas9 enzyme to the target DNA sequence for cleavage.

Question 18

A population of mosquitoes is engineered with a gene drive to resist malaria. What is the expected outcome after several generations?

Accepted Answer

The resistance gene will spread rapidly through the population, even if it does not confer a fitness advantage.

Question 19

Which of the following is a key innovation that made CRISPR-Cas9 genome editing more efficient in the laboratory?

Accepted Answer

The fusion of crRNA and tracrRNA into a single guide RNA (sgRNA).

Genetic Engineering Tools: Reporter Genes, CRISPR-Cas9, and Gene Drive Systems

Study Guide - Practice Questions

Study Guide - Flashcards