Causes of Mutation

Question 1

When can Mutations occur?

Answer 1

Spontaneously during DNA replication.

Question 2

Describe spontaneous mutation

Answer 2

Are permanent changes in DNA that occur without any outside influence.

Question 3

What is the frequency of mutations like?

Answer 3

Despite being random occurrences they occur with predictable frequency. Varies from species to species but is around 1-2 per 100,000 genes per generation.

Question 4

What affects mutation rate?

Answer 4

The rate can be increased by factors known as mutagenic agents.

Question 5

Name 2 categories of mutagenic agent

Answer 5

High energy ionizing radiation 
           - alpha and beta particles, x-rays and ultraviolet 
             light
Chemicals 
           - Nitrogen dioxide 
           - benzopyrene

Question 6

Effects of benzopyrene

Answer 6

Inactivates a tumor suppressor leading to cancer

Question 7

Benefits of mutations?

Answer 7

Production of genetic diversity necessary for natural selection and speciation.

Question 8

Negatives of mutations?

Answer 8

Almost always harmful
Often produce organism less suited to environment
Mutation in body cells can affect cell division and can cause cancer