An allele that masks another is the Dominant allele. The one that is masked is called the recessive allele. An organism that has the same alleles for a particular trait is h0m0zygous. An organism that has different alleles for a particular trait is heter0zygous.
An allele is one of the chromosomal genes located at the locus of a chromosome. A complete allele refers to the genetic makeup(genotype) of an organism,
When an allele masks another, then the allele that masks the other is the dominant allele and the masked allele is the recessive allele. This characteristic occurs in a heter0zygous genotype.
Similarly, An organism that has the same alleles for a particular trait is hom0zygous which can either be hom0zygous dominant (AA) or hom0zygous recessive (aa).
An organism that has different alleles for a particular trait is heter0zygous e.g. Aa.
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