Migration rate $$\propto \frac{1}{\text{fragment size}}$$

Question 1

Which of the following best explains why genetic engineering is possible across different species?

Accepted Answer

The genetic code is universal, so DNA from any organism will produce the same protein in another organism.

Question 2

A scientist wants to produce human insulin using bacteria. Which process should they use?

Accepted Answer

Gene cloning using a bacterial plasmid as a cloning vector.

Question 3

Which enzyme is used to seal the bonds between restriction fragments when creating recombinant DNA?

Accepted Answer

DNA ligase

Question 4

What is the main advantage of using bacterial plasmids as cloning vectors?

Accepted Answer

They are easily obtained, manipulated, and rapidly multiplied in bacteria.

Question 5

During gel electrophoresis, which DNA fragments move fastest through the gel?

Accepted Answer

Shorter fragments

Question 6

Which equation best describes the exponential amplification of DNA during PCR?

Accepted Answer

The number of DNA molecules after $$n$$ cycles is $$2^n$$

Question 7

A forensic scientist analyzes DNA from a crime scene using STR markers. Why is this method highly reliable?

Accepted Answer

The probability that two unrelated individuals have the same STR markers is exceptionally small.

Question 8

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

Accepted Answer

Denaturation

Question 9

What is the function of restriction enzymes in genetic engineering?

Accepted Answer

They cut DNA at specific sequences called restriction sites.

Question 10

Which of the following is a real-world application of transgenic animals?

Accepted Answer

Producing pharmaceutical proteins for medical use.

Question 11

A plant cell is able to dedifferentiate and give rise to all specialized cell types. This process is most closely associated with:

Accepted Answer

Plant cloning

Question 12

Which technique is used to identify the location of specific mRNAs in an intact organism?

Accepted Answer

In situ hybridization

Question 13

What is the role of Taq polymerase in PCR?

Accepted Answer

It is a heat-stable DNA polymerase that synthesizes new DNA strands during PCR.

Question 14

Which of the following best describes recombinant DNA?

Accepted Answer

DNA made from two different sources.

Question 15

A researcher disables a gene in an organism to study its function. Which technique is most likely being used?

Accepted Answer

CRISPR-Cas9 gene editing

Question 16

Which equation represents the relationship between fragment size and migration rate in gel electrophoresis?

Accepted Answer

Migration rate $$\propto \frac{1}{	ext{fragment size}}$$

Question 17

Which of the following is NOT a typical application of DNA-based biotechnology?

Accepted Answer

Increasing the number of chromosomes in humans

Question 18

What is the purpose of using nucleic acid probes in gene expression studies?

Accepted Answer

To detect specific mRNAs by hybridizing with complementary sequences.

Question 19

Which process allows researchers to compare gene expression patterns in different tissues or conditions using fluorescently labeled cDNAs?

Accepted Answer

DNA microarray assay

Question 20

A scientist wants to amplify a specific DNA segment from a 40,000-year-old woolly mammoth. Which technique should they use?

Accepted Answer

Polymerase chain reaction (PCR)

DNA Tools and Biotechnology: Concepts, Techniques, and Applications

Study Guide - Practice Questions