4.2 - How did organisms become so well adapted?

Question 1

What is meant by natural selection?

Answer 1

where individuals that are better adpated to their environment are more likely to survive & pass on their genes to future generations

Question 2

What is meant by evolution?

Answer 2

change in allele frequency in a population over time (generation)

Question 3

What is a gene pool?

Answer 3

consists of all the alleles present of all of the genes in a population at a given time

Question 4

What is meant by the Hardy-Weinburg equation?

Answer 4

equation that relateds phenotype frequencies to allele frequency

Question 5

What is reproductive isolation?

Answer 5

when two populations are unable to breed with each other or they produce offspring which fail to survive

Question 6

What is speciation?

Answer 6

formation of a new species

Question 7

What does the ‘p’ in the Hardy-Weinberg equation represent?

Answer 7

frequency of dominant allele

Question 8

What does ‘p^2’ represent in the Hardy-Weinberg equation?

Answer 8

frequency of homozygous dominant individuals

Question 9

What does the ‘q’ represent in the Hardy-Weinberg equation?

Answer 9

frequency of recessive allele

Question 10

What does ‘q^2’ represent in the Hardy-Weinberg equation?

Answer 10

frequency of homozygous recessive individuals

Question 11

What does ‘2pq’ represent in the Hardy-Weinberg equation?

Answer 11

frequency of heterozygous individuals

Question 12

What can cause reproductive isolation?

Answer 12

physical barriers eg. rivers or mountains

Question 13

What is allele frequency?

Answer 13

how often an allele occurs in a gene pool

Question 14

What is evolution usually the result of?

Answer 14

natural selection

Question 15

What can evolution sometimes result in? What is this called?

Answer 15

the production for a totally new species - speciation

Question 16

What is it called when there is a change in form (behaviour or physiology) over generations of an organism?

Answer 16

evolution by natural selection

Question 17

Why does natural selection mean that only specific characteristics are passed onto offspring?

Answer 17

If a specific characteristic gives a particular organism a selective advantage, this means that the organism is more likely to survive & reproduce & pass on the advantageous alleles for the specific characteristic
organisms with the characteristic will be more common in the next generation

Question 18

For natural selection to lead to evolution, what must there be?

Answer 18

there must be some genetic variation