Question

What is a homozygous dominant genotype?

Answer 1

Alleles are often either dominant or recessive. Dominant alleles show their effect even though the individual only has one copy of the allele (also referred to as being heterozygous) and if both the alleles are present then the condition is homozygous genotype.

Complete answer:
As humans possess two copies of every chromosome, they even have two copies of every gene and locus on those chromosomes. Each of the genes on the locus is named as an allele. A person is said to have a homozygous trait if the alleles match. Homozygous alleles are found to be both dominant or recessive. When the two dominant alleles combine together to express a dominant phenotype then it is said to be a homozygous dominant allele while when the two recessive alleles combine together to express a recessive phenotype then it is said to be a homozygous recessive.
With the help of a pea plant, this fact can easily be explained. The genes for seed shape in the case of pea plants exist in two forms, one allele or form is (R) for round seed shape while the other is (r) for wrinkled seed shape. The round seed shape allele is dominant while the wrinkled seed shape allele is recessive. In a homozygous plant, the alleles for seed shape contain either of the subsequent alleles: (RR) or (rr). The homozygous dominant is (RR) while the homozygous recessive is (rr).
Offsprings are self-pollinated for successive generations to achieve a genetic state in which an individual has inherited the same sequence of DNA for a specific gene from both i.e male and female parents.
When the offspring are self-pollinated for several generations continuously then it will result in homozygosity.

Note:
Genotype is considered a genetic combination of traits in an organism. There are 3 different types of genotype observed homozygous dominant, heterozygous, and homozygous recessive. Genotype is the genetic complement of an individual with respect to one or more characters. Organisms with the same genotype are always similar in phenotype. It is present inside the body as genes are transmitted from parents to offspring. It is affected by genes. Example. TT, tt.