Question

Referring to the Rose crossing from the previous problem, answer the following questions.



What fraction are hybrid pink?

4/4
1/4
1/2

Answer 1

Answer :-

R trait is for red colour flower.

r trait is for white colour flower.

In the above cross :-

RR indicates red colour flower.

Rr indicates pink colour flower.

rr indicated white colour flower.

Fraction of hybrid pink = 2 / 4

Fraction of hybrid pink = 1 / 2

Additional information :-

This pink colour appears due to incomplete dominance of red colour flower trait over white flower trait.

Incomplete dominance is the phenomenon of neither of the two alleles being dominant so that expression in the hybrid is a fine mixture or some what intermediate between the expressions of two alleles in their homozygous states.

There are two types of a pure breeding plants, red flowered and white flowered. On crossing the two, F₁ , plants or hybrids possess pink flowers. On selfing them F₂ generation has 1 red : 2 pink : 1 white flowered with phenotypic ratio begins similar to genotypic ratio.

Answer 2

$\: \: \: \: \dfrac{1}{2}$