4.4 Genetic Diversity And Adaptation

Question 1

What is genetic diversity?

Answer 1

The number of different alleles of genes in a species or a population.

Question 2

How does genetic diversity increase?

Answer 2

• Mutations create new alleles
• Gene flow introduces new alleles via migration

Question 3

What is natural selection?

Answer 3

The process by which advantageous alleles increase in frequency in a population

Question 4

Describe the process of natural selection

Answer 4

• Random mutations produce variation in alleles
• An individual with a beneficial mutation will be more likely to survive and reproduce
• The beneficial allele is more likely to be passed on to offspring
• The beneficial allele increases in frequency over generations

Question 5

What is evolution?

Answer 5

The change in allele frequency over time

Question 6

What is stabilising selection?

Answer 6

Natural selection favours an average phenotype (the mean). The extreme phenotypes are selected against.

Question 7

In what kind of environment does stabilising selection take place?

Answer 7

Unchanging

Question 8

What is directional selection?

Answer 8

Natural selection favours one extreme phenotype. All other phenotypes are selected against.

Question 9

In what kind of environment does directional selection take place?

Answer 9

An environment that has experienced a change

Question 10

How do you make conditions aseptic when investigating microbial growth?

Answer 10

• Disinfect surfaces
• Wash hands WITH soap
• Lift petri dish lid at an angle
• Use sterile spreader
• Use sterile pipette
• Flame neck of bottle