Question

When Mendel first crossed true breeding

tall plants (TT) with true breeding short
plants (tt), why did all the offspring
come out tall?
A. Each organism inherited one dominant and one
recessive allele (Tt).
B. Each organism was true breeding.
C. Each organism inherited two dominant alleles. (TT).

Answer 1

A. Each organism inherited one dominant and one recessive allele (Tt)

“Tt” is an heterozygous genotype. So the dominant trait (being tall) showed up in all the plants.