Alleles are described as . homologous chromosomes homologous chromosomes alternate versions of a gene alternate versions of a gene alternate phenotypes alternate phenotypes environmental factors that affect gene expression

The correct answer is - alternate versions of a gene.

Explanation:

In a cell, if there are two copies of each chromosome, these are called homologous chromosomes, one come from the father and the other comes from the mother, which helps in promoting the variety and stability of a species.

Different or alternate versions of genes are possible that can result in two phenotypes for the same trait, these alternate versions called alleles. Alleles can be dominant and recessive.

light dependent reactions:

light independent reactions:

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