Take this Exam: A-Level Biology: Gene Expression and Technology | Zestly

Question 1

In genetic fingerprinting, what is the significance of Variable Number Tandem Repeats (VNTRs)?

Accepted Answer

The number of repeats at specific loci is highly variable between individuals, creating a unique profile.

Question 2

Which of the following accurately describe the function and application of DNA probes?

Accepted Answer

A DNA probe is a single-stranded sequence of DNA that is complementary to a specific target allele.

Question 3

What is the primary role of RNA interference (RNAi) in eukaryotic cells?

Accepted Answer

To inhibit gene expression by causing the degradation of specific mRNA molecules.

Question 4

Which of the following statements regarding oncogenes and tumour suppressor genes are correct?

Answer

Oncogenes are mutated forms of proto-oncogenes that lead to uncontrolled cell division.

Answer

Tumour suppressor genes promote cell division when they are mutated.

Answer

A mutation in a tumour suppressor gene can lead to cancer if the cell loses its ability to stop the cell cycle.

Answer

Proto-oncogenes normally code for proteins that stimulate cell division.

Answer

Oncogenes are always inherited from parents and are present in every cell of the body.

Question 5

What is the purpose of a marker gene in recombinant DNA technology?

Answer

To increase the efficiency of the restriction enzyme cutting process.

Answer

To identify which host cells have successfully taken up the recombinant plasmid.

Answer

To ensure the target gene is expressed at high levels in the host.

Answer

To prevent the host cell from destroying the foreign DNA.