Lesson 13 - Calculating genetic biodiveristy

Question 1

Why do scientists calculate genetic biodiversity?

Answer 1

• Monitor health of the population and ensure its long-term survival.

Question 2

Genes vs alleles?

Answer 2

• All members of the same species have have the same genes.
• Have different alleles.

Question 3

More alleles in a population…

Answer 3

greater genetic biodiversity.

Question 4

Factors that affect genetic biodiversity:

Answer 4

Increase:
- Interbreeding between different populations. –> alleles transferred between different populations (gene flow).

• Mutations in the DNA of an organism, creating new allele.

Decrease:
- Selective breeding

• captive breeding programmes
• Rare breeds
• Artificial cloning
• natural selection
• genetic bottleneck
• Founder effect
• Genetic drift

Question 5

How do scientists measure genetic biodiversity?

Answer 5

• Measuring polymorphism. (eg. immunoglobulin gene for determining blood types)

Question 6

Three alleles for determining blood type?

Answer 6

I^A - resulting in the production of antigen A

I^B - resulting in the production of antigen B

I^O - resulting in the production of neither antigen

Question 7

If a gene is not polymorphic, it is…

Answer 7

monomorphic –> basic structure of individuals within a species remains constant.

Question 8

Equation to work out the proportion of genes that are polymorphic

Answer 8

proportion of polymorphic gene loci =

number of polymorphic gene loci / Total number of loci

Question 9

Technique used to separate fragments of DNA based on size?

Answer 9

Gel electrophoresis

• Restriction enzymes cut DNA into smaller pieces - placed in gel.
• Gel is placed between positive and negative electrodes - causes negatively charged DNA to move towards the positive side.
• Smaller fragments move further through gel.
• Banding pattern produced. –> compare.