Homozygous and heterozygous are terms that are used to describe allele pairs. Individuals carrying two identical alleles ( RR or rr) are known as homozygous. While individual organisms bearing different alleles (Rr) are known heterozygous. To better understand let us consider that we have two pairs of alleles for a hair colour gene – one allele codes for brown (R) and the other allele codes for black (r). Homologous pairs of chromosomes would either consist of same alleles (both black or brown) or different alleles (black and brown). On the basis of these possible outcomes, we can differentiate whether they are same alleles, i.e. homozygous or different alleles i.e. heterozygous. In this article, let us discuss the difference between homozygous and heterozygous.
Homozygous vs Heterozygous
|Homozygous consists of two copies of the same allele that codes for a particular trait.||Heterozygous consists of two different copies of alleles that code for a particular trait.|
|Consist of either dominant or recessive allele pairs but not both||Consist of both dominant and recessive allele pairs|
|Self-breeding results in the same traits over generations||Self-breeding results in the combination of traits|
|Produces a single gamete||Produces two types of gametes|
|The two types of homozygous alleles are homozygous-dominant and homozygous-recessive||The three types of heterozygous alleles complete dominance, incomplete dominance, and codominance|
From the differences listed above, we can conclude that homozygous and heterozygous are the two genetic terms used in the identification of traits, occurring in an organism. A trait which is either a combination of a series of dominant or regressive alleles is produced when two organisms breed. The way these alleles are combined will identify themselves as either homozygous or heterozygous. To learn more differences like the difference between genotype and phenotype, Visit Byju’s.