Recombinant DNA Technology (Batch Covid)

What is the importance of restriction endonucleases in a bacterial cell?

• It enables bacterial autolysis to occur.

• It provides resistance against antibiotics.

• It destroys antigens and neutralizes toxin.

• It cuts viral DNA molecules into fragments.

Which of following statements regarding cDNA is TRUE?

• They are usually single-stranded DNA.

• They contain both intron and exon.

• They are composed of DNA fragments synthesised using RNA polymerase.

• They contain DNA fragment complementary to mRNA.

Which of the followings is NOT a step that involved in gene cloning?

• Cut the plasmid and target DNA with modifying enzyme.

• Screen the bacterial cell that contain recombinant DNA.

• Insert DNA fragments into open plasmid and join them using DNA ligase.

• Isolate the plasmid from bacterial cell and target DNA from donor cell.

All of the following sequences are palindromic EXCEPT

• 5’ -GATC- 3’

  3’ -CTAG-5’

• 5’ -GAATTC- 3’

  3’ -CTTAAG-5’

• 5’ -AAGCTT- 3’

  3’ -TTCGAA-5’

• 5’ -CGTAA- 3’

  3’ -GCATT-5’

FIGURE 2 shows the structure of plasmid. What makes plasmid a good cloning vector?

• Able to accept foreign DNA in lacZ

• Able to receive the recombinant DNA through transformation

• Able to accept foreign DNA in multiple cloning site (MCS)

• Able to maintain the structure of the foreign gene

In production of human insulin, why mRNA is used instead of DNA molecule?

• Because plasmid cannot accept foreign DNA in MCS

• Because DNA will be degraded by enzyme found in bacteria

• Because mRNA lack exons

• Because there is no RNA splicing in bacteria

One of the steps in gene cloning is screening. Screening is done by culturing bacteria in medium agar containing ampicillin and X-gal. State the importance of ampicillin and X-gal in this medium.

• to identify host cell containing the recombinant DNA

• to identify host cell containing plasmid

• to identify host cell with DNA

• to identify host cell that able to produce β-galactosidase

Unpaired nucleotides produced by restriction enzyme at one end of DNA fragment is known as the

• blunt end

• sticky end

• restriction fragment

• single strand template

In nature, restriction enzymes are meant to protect …

• viruses from bacteria.

• bacteria from viruses.

• plants from bacteria.

• humans from viruses.

When conducting a gene cloning procedure, a scientist may eliminate the group of bacteria without any plasmid by using …

• EcoRI.

• ampicillin.

• X-gal.

• insulin