Which of the following are true of dominant and recessive alleles?
Choose 2 answers:
Choose 2 answers:
(Choice A) Only dominant alleles determine phenotype
A
Only dominant alleles determine phenotype
(Choice B) Dominant and recessive alleles can be found in the same individual
B
Dominant and recessive alleles can be found in the same individual
(Choice C) Dominant alleles mask the expression of recessive alleles
C
Dominant alleles mask the expression of recessive alleles
(Choice D) Only recessive alleles determine phenotype
D)Only recessive alleles determine phenotype

Why A is wrong: dominant alleles arent the only alleles that can determine phenotype. If someone has two recessive alleles, they will show the recessive trait.

Why B is right: Dominant and recessive alleles can be found in the same person. This is called being heterozygous. For example, brown eyes (BB) are dominant over blue (bb). Someone who has both alleles will be Bb, but will still display the dominant phenotype.

Why C is right: Dominant alleles, like the name says, are dominant over excessive alleles. While one can have both, they cannot express both. A dominant allele will mask a recessive allele.

Why D is wrong: Like my explanation for A, recessive alleles arent the only alleles that can determine phenotype. If someone has a dominant allele, they will express the dominant trait.