Merlin the magician is trying to impress his friend by crossing homozygous blue flowers with homozygous green flowers and producing brown flowers. Merlin’s friend is a geneticist, however, and is not impressed so she confronts him and explains it is not magic at all.

Question

a) What kind of dominance would the friend say this is?
b) Draw a cross and Punnett square to show the inheritance (use the format shown in the text).

Answer 1

a) The friend would say this is an example of incomplete dominance.

b)

Cross: Homozygous blue (BB) x Homozygous green (GG)

Punnett square:

| B | B
---------|--------|--------
G | BG | BG
---------|--------|--------
G | BG | BG

The Punnett square shows that all the offspring will have the genotype BG, resulting in the production of brown flowers.