Penetrance In a certain breed of plants, thorns are determined by the dominant allele T and thornless is determined by the recessive allele t. T is 60% penetrant in the heterozygote; 40% of heterozygotes will appear thornless. If you make the parental cross TT x tt; what would be the expected number of progeny for each phenotype in a population of 400 F2 plants?

The Thorn plants will be about 300 while the thornless plants will be about 100.

Explanation:

When the parents cross

TT x tt

F1; Tt, Tt,Tt, Tt.

Tt x Tt

F2;. TT, Tt, Tt, tt..

Phenotypic ratio; 3:1.

Hence,3/4* 400=300

1/4*. 400=100

linnaeus is the father of taxonomy, which is the system of classifying and naming organisms. one of his contributions was the development of a hierarchical system of classification of nature. today, this system includes eight taxa: domain, kingdom, phylum, class, order, family, genus, and species.