week 8 part 3 gene interactions

Question 1

wild type allele

Answer 1

Prevalent allele in a population

o In most cases, encodes a protein that is made in their proper amount and functions normally

o Normal Allele

Question 2

mutant alleles

Answer 2

Alleles that have been altered by mutation

o Tend to be rate in natural populations

Question 3

incomplete dominance

Answer 3

Heterozygotes exhibited a phenotype that is distinct and intermediate between the two homozygous phenotypes

o Different phenotypes are observed with 100%, 50% and 0% protein level

o 1:2:1 ratio

· Degree to which we identify incomplete dominance may depend on how closely we examine an individual’s phenotype

o Eg. Phenylketonuria (PKU)

§ Heterozygotes appear phenotypically normally but have double the normal phenylalanine blood leve

Question 4

codominance

Answer 4

Many genes have three or more variants in a population (= multiple alleles)

o Phenotype depends on which two alleles are inherited

single individual express both alleles in a way that leads to both traits in the phenotype

Question 5

complex traits

Answer 5

gene interaction and epistatic gene interaction

Question 6

gene interaction

Answer 6

occurs when a single character is controlled by the products of two or more genes

Question 7

epistatic gene interaction

Answer 7

the alleles of one gene mask the expression of the alleles of another gene