Question

I read in my book that two alleles are considered to be homozygous if they are identical. But at the same time I read the definition of allele to be:

genes which code for a pair of contrasting traits are called alleles
My doubt is that how can they be both contrasting (different) and identical (same) at the same time
What I think is that if homozygous is somehow a part of specific conditions in alleles then how can it be different from alleles itself.

Answer 1

Alleles can be both identical and contrasting at the same time based on their specific sequences and variations. Homozygous alleles are identical, while heterozygous alleles are contrasting. The terms homozygous and heterozygous describe the combination of alleles an organism carries.

Step-by-step explanation:

Alleles are different versions of genes, and an organism can have two alleles for a specific gene. Homozygous alleles are referred to as identical because they have the same gene sequence and code for the same trait. However, alleles can still be contrasting or different in terms of their specific sequence and the variations they encode. The terms homozygous and heterozygous describe the combination of alleles an organism carries. Homozygous organisms have two identical alleles, while heterozygous organisms have two different alleles.