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Course: UP Class 12th Biology > Unit 4

Lesson 1: Inheritance of one gene

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Multiple alleles, incomplete dominance, and codominance

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In humans, three alleles affect blood type. The A and B alleles are codominant and the O allele is recessive.

Which of the following answer choices is true?

(Choice A)
Human blood type is an example of incomplete dominance.
(Choice B)
The O blood type is the least common in the human population.
(Choice C)
Human blood type is an example of multiple allele inheritance.
(Choice D)
The A and B alleles are codominant because both alleles are simultaneously expressed in the heterozygote.