Population Genetics

Question 1

Define the gene pool.

Answer 1

The alleles of all the genes in the population.

Question 2

What regulates the gene pool?

Answer 2

The environment exerts selection pressures which regulate the frequency of alleles in the gene pool, as some are adapted to survive the selection pressures so the alleles determining the adaptation are selected for.

Question 3

How can allele frequencies be expressed?

Answer 3

As a proportion or percentage of the total number of copies of all alleles for that gene.

Question 4

What are the conditions under which the Hardy-Weinberg principle operates?

Answer 4

• no mutation
• no immigration/emigration
• random mating
• no selection pressure against any phenotype
• population is large (over 100+)

Question 5

What is the Hardy Weinberg equation?

Answer 5

P2 + 2PQ + Q2 = 1

Question 6

What do P and Q stand for?

Answer 6

P = dominant
Q = recessive

Question 7

What is p+q?

Answer 7

1.

Question 8

What is p2, 2PQ and q2?

Answer 8

P2 = frequency of homozygous dominant
2PQ = frequency of heterozygous
Q2 = frequency of homozygous recessive

Question 9

Define genetic drift

Answer 9

The chance variation aka alleles not being passed on by chance in the allele frequency of a population.