7.2 Populations

Question 1

What are populations?

Answer 1

groups of organisms of the same species that occupy a particular space at a particular time and that can potentially interbreed. Any species exists as one or more populations

Question 2

What are gene pools?

Answer 2

all the alleles of all the genes of all the individuals in a population at a given time

Question 3

What is allele frequency?

Answer 3

the number of times an allele occurs within the gene pool

Question 4

What is a species?

Answer 4

a group of organisms that can interbreed to produce fertile offspring

Question 5

What is the Hardy Weinberg principle?

Answer 5

allows us to estimate the frequency of alleles, genotypes and phenotypes in a population to see whether any changes are occurring over time

Question 6

What assumptions are made by the Hardy Weinberg principle?

Answer 6

• No mutations occur
• No migration in or out of the population
• No selection, so alleles are all equally passed on to the next generation
• Random mating
• Large population

Question 7

Explain the Hardy Weinberg equation for calculating allele frequency.

Answer 7

The frequency of each allele for a characteristic must add up to 1.0. The equation is therefore; p+q=1
Where p = frequency of the dominant allele and q = the frequency of the recessive allele

Question 8

Explain the Hardy Weinberg equation for calculating genotype frequency.

Answer 8

The frequencies of each genotype for a characteristic must add up to 1.0. The equation is therefore; p²+2pq+q²=1
Where p²=frequency of homozygous dominant, 2pq=frequency of heterozygous, and q²=frequency of homozygous recessive