What are 2 ways alleles can be homozygous?
To understand how alleles can be homozygous, we need to first understand what alleles are. Alleles are different versions of a gene that can occupy the same position, or locus, on a chromosome. For a particular gene, an individual inherits two alleles - one from each parent.
Now, let's explore the two ways by which alleles can be homozygous:
1. Homozygous Dominant (AA): In this case, both alleles at a given gene locus are the same and represent the dominant trait. For example, if we consider the gene for eye color, and both alleles are "A", the individual will have brown eyes. The dominant allele (A) masks the presence of the recessive allele (a).
2. Homozygous Recessive (aa): In this case, both alleles at a given gene locus are the same and represent the recessive trait. Using the same example of eye color, if both alleles are "a", the individual will have blue eyes. Since the recessive allele (a) does not have a dominant counterpart, it will express itself.
These two examples illustrate how alleles can be homozygous, meaning they are the same at a specific gene locus. To determine if given alleles are homozygous, you would need to know the genetic information of both parents and examine the genetic makeup of the individual in question.