Question

Difference between homozygous and heterozygous individual

Answer 1

the long, twisty helix that is human DNA might be one of the greatest mysteries in the universe. It’s no surprise that the study of genetics is a complex field. One concept that is sometimes confusing is the difference between homozygous and heterozygous.

t hen it comes to genetic traits, scientists look at genes and the locus where that gene or trait encodes on the chromosome. Since humans possess two copies of each chromosome, they also have two copies of each gene and locus on those chromosomes. Each of these trait-encoding genes (or loci) is called an allele. If the alleles match, the person is homozygous for that trait. If the alleles are different, the person is heterozygous for that trait.

Answer 2

There is a little bit of confusion here it seems.

Homozygous and Heterozygous are the two of the few types of genotypic combinations that lead to the production of individuals with different kinds of phenotypes that is, physical appearances.

The differences between homozygous and heterozygous genotypic combinations are as follows-

Homozygous :-

• Homozygous combinations of genes constitute genotypes that are made up of wild, original, non mutated, dominant alleles only.
• Homozygous combinations are found in the progeny that are produced as a result of pure breeding or true breeding or genetic selfing of pure-line parents.
• The progeny produced through pure breeding are referred to as "Pure-line individuals".
• Examples of homozygous combinations are as follows-

1. In the context of height, TT (Homozygous tall) and tt (Homozygous dwarf).
2. In the context of colour of flowers, RR (Homozygous red) WW (Homozygous white).

Heterozygous :-

• Heterozygous combinations of genes constitute of genotypes that are made up of a mixture of both, wild, original, non mutated, dominant genes, and mutated, recessive alleles.
• Heterozygous combinations are found in the progeny that are produced as a result of impure breeding or genetic crossing of pure-line parents.
• Only the wild, original, non mutated, dominant allele is able to express itself in phenotypes of such genotypic combinations.
• Examples of heterozygous combinations are as follows-

1. In the context of height, Tt (Heterozygous tall), heterozygous combinations can never produce dwarf plants.
2. In the context of eye colour Bb (Brown eyes), heterozygous combinations can never produce blue eyes.