Question

Radish color is controlled by a gene that exhibits incomplete dominance; purebred red radishes (RR) crossed with purebred white radishes (WW) make purple radishes (RW). What are the chances of producing purple offspring when you cross two purple parents?

Answer 1

1/2

Step-by-step explanation:

This question involves a single Gene coding for fruit color in radish plants. The gene exhibits incomplete dominance where the allele for red radish (R) and the allele for white radish (W) forms a hybrid with a purple radish (RW).

If a purebred red radish (RR) is crossed with purebred white radishes (WW), purple radishes (RW) will be formed. However, when the purple radishes are self-crossed i.e. RW × RW, the following gametes will be produced- R and W.

Using these gametes in a punnet square (see attached image), the following offsprings will be produced in the following proportions:

RR - red = 1/4

RW - purple = 2/4 or 1/2

WW - white = 1/4

Hence, the chances of producing purple offspring when you cross two purple parents is 1/2.