Question 1

Which of the following best describes the process of creating recombinant DNA?

Accepted Answer

Joining DNA fragments from two different sources using restriction enzymes and ligase

Question 2

Why are restriction enzymes crucial for genetic engineering?

Accepted Answer

They cut DNA at specific palindromic sequences, allowing precise manipulation of genes

Question 3

A scientist wants to clone a gene into a plasmid. Why must both the gene and the plasmid be cut with the same restriction enzyme?

Accepted Answer

To create complementary sticky ends that can be joined together by ligase

Question 4

Which of the following is NOT a required component for a Polymerase Chain Reaction (PCR)?

Accepted Answer

Restriction enzyme

Question 5

During PCR, what is the purpose of the denaturation step at $$95\ ^\circ\mathrm{C}$$?

Accepted Answer

To separate the double-stranded DNA into single strands

Question 6

Agarose gel electrophoresis separates DNA fragments based on which property?

Accepted Answer

Size (length in base pairs)

Question 7

Which of the following best explains why E. coli is commonly used in biotechnology?

Accepted Answer

It is a well-studied model organism that grows rapidly and is easy to manipulate genetically

Question 8

What is the function of the selectable marker gene in a plasmid used for cloning?

Accepted Answer

It allows identification of cells that have taken up the plasmid

Question 9

If a scientist wants to produce large quantities of a human protein, which sequence of steps would be most appropriate?

Accepted Answer

Insert the human gene into a plasmid, transform E. coli, and grow the bacteria

Question 10

Which of the following equations correctly represents the theoretical number of DNA molecules after $$n$$ cycles of PCR, starting from a single molecule?

Accepted Answer

$$2^n$$

Question 11

Why must PCR primers be complementary to sequences flanking the target DNA region?

Accepted Answer

So that DNA polymerase can extend from the primers and amplify only the region of interest

Question 12

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

Accepted Answer

It forms covalent bonds between adjacent nucleotides, sealing nicks in the sugar-phosphate backbone

Question 13

A researcher wants to confirm the success of a PCR reaction. Which technique should they use?

Accepted Answer

Agarose gel electrophoresis

Question 14

Which of the following is a real-world application of recombinant DNA technology?

Accepted Answer

Production of human insulin in bacteria

Question 15

Which property of restriction enzyme recognition sites is essential for their function in cloning?

Accepted Answer

They are palindromic sequences

Question 16

During the production of recombinant human insulin, why are the A and B chains produced separately in bacteria?

Accepted Answer

To allow proper folding and formation of disulfide bonds after purification

Question 17

Which of the following best explains why high temperatures are used in the denaturation step of PCR?

Accepted Answer

High temperatures break hydrogen bonds between DNA strands, resulting in single-stranded DNA

Question 18

A plasmid used for cloning in the lab contains an origin of replication. What is the function of this sequence?

Accepted Answer

It allows the plasmid to be replicated within the host cell

Question 19

Which of the following steps is NOT part of the Polymerase Chain Reaction (PCR) cycle?

Accepted Answer

Ligation of DNA fragments

Question 20

A scientist wants to separate and visualize DNA fragments after a restriction digest. Which technique should they use?

Accepted Answer

Agarose gel electrophoresis

Week 9 - Nov 3&5

Study Guide - Practice Questions

Study Guide - Flashcards