Which genetic scenario describes both alleles being fully and simultaneously expressed in the phenotype?

Prepare for the Abeka Biology Test 3 with our extensive resources. Engage in flashcards and multiple choice questions, each offering hints and thorough explanations to ensure success. Equip yourself with essential knowledge and excel in your exam!

Multiple Choice

Which genetic scenario describes both alleles being fully and simultaneously expressed in the phenotype?

Explanation:
When looking at how alleles are expressed in a heterozygous individual, codominance is the pattern where both alleles are shown fully and at once in the phenotype. A classic example is the ABO blood types: an individual with one A allele and one B allele expresses both A and B antigens, resulting in the AB blood type. This stands in contrast to incomplete dominance, where the heterozygote shows an intermediate trait (like a pink flower from red and white). It also differs from homozygous, where both alleles are the same, so only one form is produced, and from a dominant allele masking the other, where only the dominant trait appears.

When looking at how alleles are expressed in a heterozygous individual, codominance is the pattern where both alleles are shown fully and at once in the phenotype. A classic example is the ABO blood types: an individual with one A allele and one B allele expresses both A and B antigens, resulting in the AB blood type. This stands in contrast to incomplete dominance, where the heterozygote shows an intermediate trait (like a pink flower from red and white). It also differs from homozygous, where both alleles are the same, so only one form is produced, and from a dominant allele masking the other, where only the dominant trait appears.

Subscribe

Get the latest from Passetra

You can unsubscribe at any time. Read our privacy policy