Question

The trait for flower color in a plant has red and white alleles. The red color is the dominant trait. What is the phenotypic ratio for a cross between plants with red (Rr) flowers and red (Rr) flowers?

4 red : 0 white
3 red : 1 white
2 red : 2 white
1 red : 1 white

Answer 1

3 red flowers, 1 white

Step-by-step explanation:

R r

R RR Rr

r Rr rr

Lowercase r is white flower, Uppercase R is red flower. Since R is dominant, we only need one uppercase R for the flower to be red. For the flower to be white, both alleles must be lowercase r, since r is recessive.

Answer 2

it would be 3 red : 1 white