The color of the petals in a carnation is determined by an incomplete dominance pattern. The Punnett square is used to determine the genotypes of the offspring of a homozygous red (RR) and a homozygous white (rr) carnation.

Question

According to the Punnett square, what color of petals could result from the pairing of these plants?

A.
only red flowers

B.
only pink flowers

C.
white and red flowers

D.
red and pink flowers

Answer 1

In a situation of incomplete dominance, the offspring exhibit a blending of characteristics from both parents. If you cross a homozygous red carnation (RR) with a homozygous white carnation (rr), the resulting offspring will have the genotype Rr, which corresponds to a pink flower color.

The Punnett square for this cross would look like this:

    R   R
  _______
r | Rr | Rr |
  _______
r | Rr | Rr |
  _______

All offspring will have the genotype Rr, resulting in only pink flowers.

Therefore, the correct answer is:

B. only pink flowers.