Which best describes a recessive allele?

Question

always inherited from a parent when a dominant allele is inherited from the other parent
never inherited from a parent when a dominant allele is inherited from the other parent
only determines phenotype when a dominant allele for the same trait is present
does not determine phenotype when a dominant allele for the same trait is present

Answer 1

The best description of a recessive allele is:

does not determine phenotype when a dominant allele for the same trait is present.

Recessive alleles only express their traits phenotypically when an individual has two copies of the recessive allele (homozygous recessive). If a dominant allele is present, it will mask the expression of the recessive allele.