4.4 - Genetic diversity and adaptations

Question 1

Define genetic diversity

Answer 1

no. of different alleles of genes in a population
- enables natural selection to occur

Question 2

Types of adaptations caused by natural selection

Answer 2

• anatomical: physical structures
• physiological: processes within the body
• behavioural: actions (can be learnt or inherited)

Question 2

What is the Founder effect?

Answer 2

small no. of individuals from large parent population start a new population
- so small gene pool

Question 3

Define gene pool

Answer 3

complete range of alleles that exist in all the individuals of a population/species

Question 4

Define genetic drift

Answer 4

gradual change in allele frequencies in small population due to chance (not natural selection)

Question 5

Define genetic bottleneck

Answer 5

• when previously large population suffers a dramatic fall in numbers e.g by a natural disaster
• reduces genetic diversity in population as alleles are lost
• surviving individuals breed and reproduce with close relatives

Question 6

Describe aseptic techniques

Answer 6

• disinfect all surfaces and equipment
• use Bunsen burner in the work space so convection currents draw microbes away from culture
• flame wire hoop before using
• flame neck of any bottles to prevent any bacteria
  entering
• keep all vessels containing bacteria open for min. time
• close windows and doors to limit air currents