Q: Which equation best represents the process of ligating compatible DNA fragments during cloning?

$$\text{DNA fragment A} + \text{DNA fragment B} \xrightarrow{\text{DNA ligase}} \text{Recombinant DNA}$$

Question 1

Which of the following best describes the main difference between traditional selective breeding and modern genetic engineering in the context of crop improvement, as illustrated by the domestication and modification of corn?

Accepted Answer

Genetic engineering allows for the introduction of genes from unrelated species, while selective breeding relies on crossing individuals within the same species.

Question 2

A scientist wants to produce a human protein in E. coli. Which of the following steps is NOT necessary in the process of recombinant DNA technology?

Accepted Answer

Allowing E. coli to naturally mutate until it expresses the human protein.

Question 3

Which feature of a plasmid vector ensures that only bacteria containing the plasmid will grow on selective media?

Accepted Answer

Selectable marker

Question 4

Restriction enzymes are essential tools in genetic engineering. What is their primary function?

Accepted Answer

To cut DNA at specific palindromic sequences, generating fragments with sticky or blunt ends.

Question 5

In blue/white screening, what does the appearance of white bacterial colonies on X-gal media indicate?

Accepted Answer

The lacZ gene is disrupted by the insertion of foreign DNA, indicating the presence of recombinant plasmids.

Question 6

Which of the following is a real-world example of a therapeutic protein produced using recombinant DNA technology?

Accepted Answer

Human insulin (Humulin)

Question 7

A plasmid vector contains a multiple cloning site (MCS). What is the main advantage of this feature?

Accepted Answer

It provides several unique restriction sites for the insertion of foreign DNA.

Question 8

Which equation best represents the process of ligating compatible DNA fragments during cloning?

Accepted Answer

$$	ext{DNA fragment A} + 	ext{DNA fragment B} \xrightarrow{	ext{DNA ligase}} 	ext{Recombinant DNA}$$

Question 9

Why is cDNA (complementary DNA) often used instead of genomic DNA when expressing a human gene in bacteria?

Accepted Answer

cDNA contains only exons and lacks introns, which bacteria cannot process.

Question 10

Which of the following best explains why methylation of bacterial DNA is important in the context of restriction enzymes?

Accepted Answer

Methylation protects bacterial DNA from being cut by their own restriction enzymes.

Question 11

A researcher wants to express a gene only when bacteria are exposed to a specific chemical. Which plasmid feature should she use to control gene expression?

Accepted Answer

Inducible promoter

Question 12

Which of the following is NOT a typical application of genetically modified organisms (GMOs)?

Accepted Answer

Increasing the mutation rate in wild populations

Question 13

A scientist uses EcoRI to cut both a plasmid and a gene of interest. What property of EcoRI ensures that the gene can be inserted into the plasmid?

Accepted Answer

EcoRI creates compatible sticky ends on both the plasmid and the gene.

Question 14

Which of the following best describes the role of the Shine-Dalgarno sequence in an E. coli expression vector?

Accepted Answer

It facilitates efficient translation initiation in bacteria.

Question 15

A patient with diabetes is prescribed Humulin. Which statement best explains why Humulin is considered a biotechnological product?

Accepted Answer

It is produced by genetically modified bacteria expressing the human insulin gene.

Question 16

Which of the following steps in gene cloning ensures that only bacteria containing recombinant plasmids are identified?

Accepted Answer

Plating bacteria on media with antibiotics and X-gal, then selecting white colonies.

Question 17

Which of the following equations best represents the transformation process in bacteria?

Accepted Answer

$$	ext{Bacteria} + 	ext{Recombinant Plasmid} ightarrow 	ext{Transformed Bacteria}$$

Biotechnology and Genetic Engineering: Principles and Applications

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