Question

Suppose the two possible alleles for the height gene are tall and short. If short is recessive to tall, provide the symbol representation and the phenotype for each of the genotype for this trait.

Answer 1

The alleles for short will be tt and for tall TT

Explanation:

The recessive alleles are written in small alphabets in Mendelian genetics so the alleles for short is tt.

They must be homozygous to express the phenotypic trait of short height in progeny.

tt = short

suppose if a homozygous tall and homozygous short is crossed

all the progeny will be heterozygous tall. Tt 4:0 ( no short progeny)

Suppose Tt is crossed with Tt

If heterozygous tall are crossed then genotype ratio will be

Tt:TT:tt

2:1:1

This means only 25% will be short.