[23] Mutagenesis

Question 1

What is mutagenesis?

Answer 1

It’s the process by which the genetic information of an organism is changed, resulting in a mutation.

Question 2

What are the two types of mutagenesis?

Answer 2

• Site-directed mutagenesis
• Random mutagenesis

Question 3

What is site-directed mutagenesis?

Answer 3

A method used to make specific and intentional changes to the DNA sequence of a gene.

Question 4

What is random mutagenesis?

Answer 4

A process by which random mutations are introduced into a DNA sequence.

Question 5

What are the applications of mutagenesis?

Answer 5

• Studying gene function
• Developing disease models
• Creating organisms with desirable traits

Question 6

What is a point mutation?

Answer 6

A type of mutation where a single nucleotide base is changed, inserted, or deleted.

Question 7

What are the three types of point mutations?

Answer 7

• Missense mutation
• Nonsense mutation
• Silent mutation

Question 8

What is a missense mutation?

Answer 8

A type of point mutation where one DNA base pair is changed, resulting in a different amino acid.

Question 9

What is a nonsense mutation?

Answer 9

A point mutation where a codon that specifies an amino acid is changed into a stop codon.

Question 10

What is a silent mutation?

Answer 10

A point mutation where a DNA base pair is changed, but the altered codon still codes for the same amino acid.

Question 11

What is an insertion mutation?

Answer 11

A mutation where one or more nucleotides are added to a DNA sequence.

Question 12

What is a deletion mutation?

Answer 12

A mutation where one or more nucleotides are removed from a DNA sequence.

Question 13

What is a frameshift mutation?

Answer 13

A type of mutation caused by insertions or deletions, where the number of DNA bases is not a multiple of three.

Question 14

What is a conditional mutation?

Answer 14

A mutation that produces a phenotype under certain environmental conditions.

Question 15

What is a lethal mutation?

Answer 15

A mutation that results in a phenotype capable of causing the death of an organism.

Question 16

What is a suppressor mutation?

Answer 16

A mutation that reverses the effect of a previously existing mutation in a different location.

Question 17

What is an induced mutation?

Answer 17

A mutation that results from exposure to certain physical or chemical agents called mutagens.

Question 18

What is a spontaneous mutation?

Answer 18

A mutation that arises naturally and not as a result of exposure to mutagens.

Question 19

What are mutagens?

Answer 19

Agents, such as radiation or chemicals, that can induce or increase the frequency of mutation in organisms.

Question 20

What is a reverse mutation (reversion)?

Answer 20

A second mutation event that restores the original sequence and hence the original phenotype.