genetic diversity and adaptation

Question 1

define genetic diversity

Answer 1

number of different alleles of genes in a population

Question 2

define allele

Answer 2

variations of a gene

Question 3

why is genetic diversity advantageous

Answer 3

enables natural selection to occur

Question 4

how does natural selection work

Answer 4

1. random mutation can result in new alleles of a gene
2. in certain environments, new allele is advantageous, so possessor is mroe likely to survive and reproduce
3. advantageous allele is inherited by off spring
4. over many generations, the new allele increases in frequency in the population

Question 5

what can adaptations be?

Answer 5

anatomical
physiological
behavioural

Question 6

what is directional selection?

Answer 6

selection favours one extreme phenotype

normal distribution curve shifts in direction of this phenotype

Question 7

what is stabilising selection?

Answer 7

the middle trait/average phenotype has the selective advantage
variation of traits decreases over generations

Question 8

antibiotics resistance in bacteria

Answer 8

random mutation creates a resistance allele in the bacterial population
when exposed to antibiotic, only those with resistance allele will survive and reproduce
resistance allele frequency increases over generations

Question 9

how does human birth weight exemplify stabilising selection

Answer 9

a middle birth wright has a selective advantage

mroe likely to survive and reproduce to pass on allele to offspring