Using “T” to represent a dominant allele (version) of a gene and “t” for the recessive allele:
Which of the below combinations is homozygous dominant? ______
Which of the below combinations is homozygous recessive? ______
Which of the below combinations is heterozygous? ______
T T T t t t
The combination T T is homozygous dominant.
The combination t t is homozygous recessive.
The combination T t is heterozygous.