Answer to Question #87447 in Genetics for Bryan McCollaum

Question

The gene for tallness (T) in a pea plant is dominant over the gene for shortness (t). The Punnett square below shows the cross between two tall pea plants (Tt). What is the phenotypic ratio of the offspring produced as a result of the cross?

Answer 1

The cross between two heterozygous plants (Tt) will lead to the production of the offspring with the following genotypes ratio:

Tt × Tt → TT + 2Tt + tt.

The plants with genotypes TT and Tt are tall as T allele is dominant. As a result, the phenotypic ratio of the offspring is tall:short = 3:1

Answer: 3:1