7.2 Populations

Question 1

Define species

Answer 1

A group of organisms that can interbreed to produce fertile offspring

Question 2

Define population

Answer 2

All the organisms of a particular species that live in the same place

Question 3

Define gene pool

Answer 3

All of the alleles existing for a particular locus within a population

Question 4

Define allele frequency

Answer 4

The proportion of a certain allele within a gene pool, expressed as a decimal or percentage

Question 5

What is the Hardy-Weinberg principle?

Answer 5

Allows us to estimate the frequency of alleles in a population, as well as if allele frequency is changing over time

Question 6

Give the assumptions made by the Hardy-Weinberg principle

Answer 6

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

Question 7

Explain the Hardy-Weinberg equation for calculating allele frequency

Answer 7

The frequencies of each allele for a characteristic must add up to 1.
p + q = 1
p = frequency of the dominant allele
q = 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 characteristics must add up to 1
p^2 + 2pq + q^2
p^2 = frequency of homozygous dominant
2pq = frequency of heterozygous
q^2 = frequency of homozygous recessive