Question

3. Pansies can grow to be tall (T), which is dominant, or short (t), which is recessive. They can also be red (R),

Answer 1

Answer:

Pansy 1 Genotype: TtRr

Pansy 2 Genotype: ttrr

Pansy 1 Gametes: TR, Tr, tR, tr

Pansy 2 Gametes: All tr

Phenotypic ratio of offspring: 1:1:1:1 (1 Tall red: 1 Tall white: 1 Short Red: 1 short white)

Explanation:

This is a cross involving two different genes; one coding for height and the other for colour in pansies. The allele for Tallness (T) is dominant over the allele for shortness (t) in the first gene while the allele for red color (R) is dominant over the allele for white color (r) in the second gene.

According to the question, a pansy

that is heterozygous for both traits will have a genotype: TtRr while a pansy that is homozygous recessive for both traits will have a genotype: ttrr

In a cross between a TtRr and ttrr, the following allelic combinations of gametes will be produced by each pansy;

TtRr- TR, Tr, tR and tr

ttrr- tr, tr, tr, tr

Using these gametes in a punnet square (see attached image), a phenotypic ratio 1:1:1:1 consisting of (4 Tall red: 4 Tall white: 4 Short Red: 4 short white) offsprings will be produced.