4.3 Theoretical genetics

Question 1

Define genotype

Answer 1

The alleles of an organism

Question 2

Define phenotype

Answer 2

The characteristics of an organism

Question 3

Define dominant allele

Answer 3

An allele that has the same effect on the phenotype whether it is present in the homozygous or heterozygous state

Question 4

Define recessive allele

Answer 4

An allele that only has an effect on the phenotype when present in the homozygous state

Question 5

Define codominant alleles

Answer 5

Pairs of alleles that both affect the phenotype when present in a heterozygote

Question 6

Define locus

Answer 6

The particular position on homologous chromosomes of a gene

Question 7

Define homozygous

Answer 7

Having two identical alleles of a gene

Question 8

Define heterozygous

Answer 8

Having two different alleles of a gene

Question 9

Define carrier

Answer 9

An individual that has one copy of a recessive allele that causes a genetic disease in individuals that are homozygous for this allele

Question 10

Define test cross

Answer 10

Testing a suspected heterozygote by crossing it with a known homozygous recessive