CB11 Mendelian Genetics & Inheritance Patterns

Question 1

Understand the principle of segregation

Answer 1

• The alleles of a locus segregate into separate gametes
• one gamete inherited from each parent at random

Question 2

Understand the principle of independent assortment

Answer 2

• The alleles of a locus segregate independently from those of another
• one gamete inherited from each parent at random
• parental gametes & recombinant gamete

Question 3

Understand the concept and molecular basis of dominance

Answer 3

Dominance: dominant allele will mask the effect of the recessive allele

Incomplete dominance: dominant allele will partially mask the effect of the recessive allele

Co-dominance: both alleles will show an effect

Question 4

Describe the phenotypes resulting from monohybrid cross

Answer 4

True breeding varieties (homozygous)
F1 = full dominance (100%)

F2 = 75% dominant, 25% recessive

Question 5

Describe the phenotypes resulting from dihybrid cross

Answer 5

Full dominance in F1

F2 = 9:3:3:1

Question 6

Describe the phenotype resulting from test cross

Answer 6

A test cross is a back cross allowing to determine if an individual with the dominant phenotype is homozygous or heterozygous

50:50, if the individual was heterozygous
100, if the individual was homozygous