How are DNA, the genetic code, chromosomes, and genes related?

An allele that appears or expresses itself over a recessive trait is called a dominant allele. Alleles can be dominant or recessive. Dominant alleles are responsible for dominant traits and if two dominant alleles are found together, a dominant trait will be expressed. Similarly, if two recessive alleles are found together, a recessive trait will be expressed. However, if both recessive allele and dominant allele are found together, the recessive allele will be masked by the dominant allele and a dominant trait will be expressed.

Explanation:

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