Question 1

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

Accepted Answer

They cut DNA at specific sequences, producing sticky ends for ligation.

Question 2

In the process of creating recombinant DNA, which enzyme is responsible for joining DNA fragments together?

Accepted Answer

DNA ligase

Question 3

A scientist wants to amplify a specific gene from a small blood sample. Which technique should they use?

Accepted Answer

Polymerase chain reaction (PCR)

Question 4

During PCR, what is the purpose of heating the reaction mixture to a high temperature in the denaturation step?

Accepted Answer

To separate the double-stranded DNA into single strands

Question 5

Which of the following is NOT a required component for a PCR reaction?

Accepted Answer

DNA ligase

Question 6

If you start with one double-stranded DNA molecule and perform six cycles of PCR, how many double-stranded copies of DNA will you have?

Accepted Answer

$$2^6$$

Question 7

Which property of DNA allows it to migrate toward the positive electrode during gel electrophoresis?

Accepted Answer

DNA is negatively charged and attracted to the positive anode.

Question 8

What is the main purpose of using a DNA probe in Southern blotting?

Accepted Answer

To detect specific DNA sequences by hybridization

Question 9

Short tandem repeats (STRs) are useful in DNA fingerprinting because:

Accepted Answer

They vary greatly among individuals, allowing for identification.

Question 10

Which of the following steps is NOT part of the Southern blotting procedure?

Accepted Answer

Amplifying DNA using PCR

Question 11

In dideoxy sequencing, what is the function of dideoxynucleotides?

Accepted Answer

They terminate DNA synthesis at specific bases, allowing sequence determination.

Question 12

A plasmid used in DNA cloning must have which of the following features to be effective?

Accepted Answer

All of the above

Question 13

Which of the following best explains why Taq polymerase is used in PCR?

Accepted Answer

It is stable at high temperatures required for denaturation.

Question 14

Which of the following is a real-world application of DNA cloning in medicine?

Accepted Answer

Producing human insulin in bacteria for diabetic patients

Question 15

Which step in PCR involves the binding of primers to the single-stranded DNA template?

Accepted Answer

Annealing

Question 16

What is the correct order of steps for splicing foreign DNA into a plasmid and inserting the plasmid into bacteria?

Accepted Answer

Cut plasmid with restriction enzyme, ligate foreign DNA, transform bacteria

Question 17

Which of the following is NOT a characteristic of a vector used in DNA cloning?

Accepted Answer

Is always a linear DNA molecule

Question 18

In gel electrophoresis, which DNA fragments migrate the fastest?

Accepted Answer

The smallest fragments

Question 19

Which of the following is a key difference between DNA fingerprinting and DNA sequencing?

Accepted Answer

DNA fingerprinting analyzes patterns of STRs, while DNA sequencing determines the exact nucleotide order.

Question 20

Which of the following is NOT a reason why researchers use DNA-based technologies?

Accepted Answer

To measure blood pressure

DNA Tools and Biotechnology: Study Notes

Study Guide - Practice Questions