Genetic information, variation and relationships between organisms- Genetic diversity and adaptation

Question 1

What is Genetic Diversity?

Answer 1

genetic variation, the variety of alleles within a population of a species

Question 2

Benefit of high genetic diversity?

Answer 2

species able to adapt with changes in the environment e.g. individuals will have characteristics to survive, and will reproduce passing on their alleles, so the species
does not become extinct

Question 3

What can lower genetic diversity?

Answer 3

small population size (e.g. founder effect – where the numbers
start low, or genetic bottleneck – where the numbers decrease)

Question 4

What is natural selection and adaptation?

Answer 4

 variation in population of species
(genetic diversity/genetic variation/variety in gene pool)
 new alleles arise by random mutation
 environment applies a selection pressure on the population
 those with favourable characteristics/favourable alleles/selection advantage/better
adapted survive, the others die [natural selection]
 the ones that survive will reproduce, passing on their favourable alleles
 if this happens for many generations, then that characteristic will become most common
– the allele will become more frequent [adaptation]

Question 5

What are the 2 types of selection?

Answer 5

stabilising and directional

Question 6

What is stabilising selection?

Answer 6

 when the environment favours those with the most common characteristic – those on the
extreme dies out
 the common characteristic increases in proportion
 the range (standard deviation) will reduce

Question 7

What is directional selection?

Answer 7

 when the environment favours those individuals with characteristics on one of the
extremes
 over time this will become the most common characteristic
 normal distribution will shift to that extreme