genetic diversity and natural selection

Question 1

what is genetic diversity

Answer 1

amount of different alleles in a population

Question 2

how is genetic. diversity increased in poplulation

Answer 2

mutations
different alleles being introduced by migration

Question 3

how is genetic diversity increased

Answer 3

mutations
different alleles s being introduced through migration

Question 4

effects of genetic diversity

Answer 4

-allows natural selection
-large gene pool allows for adaptation so less vulnerable to extinction

Question 5

what is genetic bottleneck

Answer 5

-an event that causes a big reduction within the population
-this reduces the number of different alleles in. the gene pool so reduces genetic diversity
-the survivors reproduce and a larger population is created from few individuals so gene pool is small(founder effcet)

Question 6

describe natural selection

Answer 6

Mutation leads to variation in a species by developing a new allele​

The new allele provides an advantage e.g. give an example from the question​

Organisms with the new allele can survive and reproduce​

Advantageous allele is passed on to offspring​

The advantageous allele increases in frequency in the population

Question 7

what is a behavioural adaptation

Answer 7

way an organism acts to increase chance of survial and reproduction e.g possums playing dead when under threat

Question 8

what is an physiological adaptation

Answer 8

processes inside and organisms body that increase chance of survival e.g bears hibernate over winter so their metabolism slows which conserves energy so they dont have to hunt

Question 9

what is a anatomical adaptation

Answer 9

structural features of an organisms body e.g polar bears white to camouflage

Question 10

what is directional selction

Answer 10

where individuals with the alleles for characteristics of an extreme type are favoured and are more likely to survive and reproduce e.g bacteria with antibiotic restistance

Question 11

what is stabilising selection

Answer 11

where individuals with alleles for the characteristic toward the middle of the range are more likely to survive and reproduce it reduces the range of possible characteristics e.g human birth rate favours median