A TT genotype is said to be?

homozygous dominant

Explanation:

AA or BB would be another example of this. Having two of either capital or lowercase letters makes it homozygous. It is dominate because their is only one type of letter; In this case it is a capital letter.

Homozygous

According to Mendelian inheritance, every trait (characteristic) of organsim is governed by pair of genes (that exist in two different forms, recessive and dominant allele).

Dominant allele (expressed in capital letter) masks the expression of recessive allele that is expressed in small letter.

There are two possible genotypes for dominant trait, such as 'tall pea plant' can be expressed by TT (homozygous dominant, since both alleles are same) and Tt (heterozygous dominant, since both are different alleles).

Thus, TT depicts homozygous dominant genotype.

(Hope this helps) Sky