Question 1

Which of the following best describes the role of restriction enzymes in recombinant DNA technology?

Accepted Answer

They cut DNA at specific sequences, creating sticky or blunt ends for cloning.

Question 2

During PCR, why is a thermostable DNA polymerase required?

Accepted Answer

Because it can withstand repeated heating and cooling cycles without denaturing.

Question 3

A scientist wants to clone a gene into a plasmid. After ligating the gene into the plasmid and transforming E. coli, what feature allows selection of bacteria that have successfully taken up the plasmid?

Accepted Answer

Presence of a selectable marker gene, such as antibiotic resistance.

Question 4

If a recombinant plasmid is cut with the same restriction enzyme used for cloning (e.g., EcoRI), how many DNA bands would you expect to see after gel electrophoresis?

Accepted Answer

Two bands of linear DNA

Question 5

Which equation best represents the exponential amplification of DNA during PCR, where $$n is $$the number of cycles?

Accepted Answer

$$2^n$$

Question 6

Which technique is most appropriate for analyzing the expression of a single gene at the RNA level?

Accepted Answer

Reverse transcription-PCR (RT-PCR)

Question 7

In Sanger sequencing, what is the function of dideoxyribonucleotides (ddNTPs)?

Accepted Answer

They terminate DNA strand synthesis at specific bases.

Question 8

Which of the following is a real-world application of expressing recombinant proteins in bacteria?

Accepted Answer

Production of human insulin for diabetes treatment.

Question 9

A scientist uses CRISPR-Cas9 to create a double-strand break in a gene. Which repair pathway often results in a loss-of-function mutation due to insertions or deletions?

Accepted Answer

Non-homologous end joining (NHEJ)

Question 10

Which method is used for genome-wide analysis of gene expression, allowing quantification of all mRNAs in a sample?

Accepted Answer

RNA-sequencing (RNA-seq)

Question 11

Short tandem repeats (STRs) are used in forensic science because:

Accepted Answer

They are unique to each individual and can be easily amplified by PCR.

Question 12

Which of the following best describes the process of gene knockout by homologous recombination?

Accepted Answer

A gene is replaced by a selectable marker through double crossover events.

Question 13

In RT-PCR, what is the purpose of using an oligo-dT primer?

Accepted Answer

To bind to the poly-A tail of eukaryotic mRNAs and initiate cDNA synthesis.

Question 14

Which of the following is NOT a typical use of recombinant DNA technology in agriculture?

Accepted Answer

Sequencing the human genome.

Question 15

A patient is tested for a disease-associated SNP. Which technique could be used to genotype the SNP?

Accepted Answer

PCR amplification and sequencing of the region containing the SNP.

Question 16

Which of the following statements about plasmids is TRUE?

Accepted Answer

Plasmids are small, circular DNA molecules that replicate independently of the bacterial chromosome.

Question 17

Which step in the PCR cycle is responsible for separating the two DNA strands?

Accepted Answer

Heating to denature the DNA.

Question 18

Which of the following is a plausible outcome of using RNA interference (RNAi) in a eukaryotic cell?

Accepted Answer

Partial or complete silencing of a specific gene's expression at the mRNA level.

Question 19

Which equation describes the relationship between the number of DNA molecules after $$n$$ cycles of PCR, starting from a single molecule?

Accepted Answer

$$N = 2^n$$

Question 20

Which of the following is a key advantage of next-generation sequencing compared to Sanger sequencing?

Accepted Answer

It allows for much faster and higher throughput sequencing of large genomes.

Lecture 22 (Unit 2)--Recombinant DNA Tools and Biotechnology: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard