Genetic Drift

Question 1

What is genetic drift?

3

Answer 1

• change allele f in pop over gen due to Ramadan events
• doesn’t depend if allele good/bad
• can’t predict which genes get passed on (random)

Question 2

When is genetic drift happening and what size of pop does it affect the strongest?

2

Answer 2

• happens all the time in all pops

- strong in small pops

Question 3

What are the 2 opportunities for genetic drift that involve a change ( decrease) in pop size?

1

Answer 3

1) bottle neck event
2) founder effect

• allele f in new diff original

Question 4

What is the bottle neck effect?

Answer 4

• pop size decreases fast in short time for at least one gen (usually from catastrophes)

Question 5

Bottle next effect with no change in allele f?

1

Answer 5

No genetic drift

• change total alleles in beginning but diversity same and when pop increases it’s the same as before

Question 6

Bottle neck with changes in allele f?

3

Answer 6

Yes genetic drift

• by chance only lucky survive
• allele f of gen 2 very diff (decrease genetic variation)
• later gen allele very diff original

Question 7

Can genetic drift happen without decrease in pop size?

Answer 7

Yes if due to random event

• (reproduction)

Question 8

What is fixation?

Answer 8

Loss 100% of an allele

Question 9

What is the founder effect?

Answer 9

• new pop is founded by few individuals
• isolated original pop (no gene flow)
• allele f picky very diff original
• some alleles may be lost ( decrease genetic variation)

Question 10

What is an invasive species an example of ?

Answer 10

Founder effect

Question 11

What can happen to allele f with genetic drift?

Answer 11

Reduction or increase in allele f

Question 12

What evolutionary mech tend increase genetic variation?

Answer 12

Mutation and gene flow