Differentiate between epistasis and dominance.

Explanation

To differentiate between epistasis and dominance, we can follow these steps:

### Step 1: Define Dominance
Dominance refers to the relationship between alleles of a single gene. In this context, one allele (the dominant allele) can mask the expression of another allele (the recessive allele). According to Mendel's law of dominance, when an organism has two different alleles for a trait, the dominant allele will determine the phenotype, while the recessive allele will not be expressed in the presence of the dominant allele.

### Step 2: Define Epistasis
Epistasis is a form of gene interaction where the expression of one gene is influenced or suppressed by one or more other genes. In this case, the phenotypic expression of a trait is not solely determined by a single gene but is affected by the interactions between multiple genes. This means that the presence of certain alleles in one gene can mask or modify the expression of alleles in another gene.

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