4.5 Genetic Diversity and Adaptation

Question 1

What does genetic diversity allow to occur?

Answer 1

Natural selection

Question 2

What are the two types of natural selection?

Answer 2

• Directional
• Stabilising

Question 3

What are the principles of natural selection in the evolution of populations?

Answer 3

1. There is existing variation within the population
2. Mutation occurs
3. Some organisms have a specific allele that helps them survive
4. Adapted organisms reproduce
5. Increased frequency of advantageous allele, decrease frequency of non-advantageous allele

Question 4

What is an example of directional selection?

Answer 4

Antibiotic resistance

Question 5

What is directional selection?

Answer 5

• selection pushes curve to the right
• often influenced by abiotic factors
• phenotypes of one extreme are selected for and the other is selected against

Question 6

What is stabilising selection?

Answer 6

• acts against both extremes
• selected for the mean
• narrower spread
  (e.g birth weights)

Question 7

What are the three types of adaptation?

Answer 7

• Anatomical (structural/physical features)
• Physiological (biological processes within the organism)
• Behavioural (mannerisms and the way the organism acts)

Question 8

What are some aseptic techniques?

Answer 8

• washing hands thoroughly
• disinfecting work surfaces
• sterilising apparatus by flaming
• having a lit blue bunsen burner to sterilise the air
• wearing gloves