4 Problem 5 What is the concept of dominance A The concept o

4.

(Problem 5) What is the concept of dominance?

A. The concept of dominance states that when two different alleles are present in a genotype, both alleles can be observed equally in the phenotype. B. The concept of dominance states that recessive alleles are only visible in the heterozygous condition. C. The concept of dominance states that when two different alleles are present in a genotype, only the dominant allele is observed in the phenotype. D. The concept of dominance states that an organism can only exhibit two alleles at a time. E. None of these statements accurately explains the concept of dominance.

For the following pedigree, give the most likely mode of inheritance, assuming that the trait is rare. 1 5 6 7 8 IV 1 3 Problem 3.38 Genetics Essentials: Concepts and Connections, Third Edition 2016 Macmillan Education A. Autosomal recessive B. X-linked recessive C. Autosomal dominant C D. Y-linked dominant C E. Y-linked recessive

Solution

Answer

40). A. Autosomal recessive

If X-linked recessive, immediate male progeny of affected female progeny are affected. But not in the pedigree, so it is not x-linked

It is not Y-linked as it appears in the males only.

It not autosomal dominant. Because, if it is autosomal dominant, most of the progeny would have the trait.

41). E. None of these statements accurately explains the concept of dominance.

Explanation:

The concept of dominance states that recessive alleles are only visible in the homozygous condition, where as dominant allele appears in both homozygous and heterozygous conditions.

AA (homozygous), Aa (heterozygous)--------dominant trait

aa (homozygous)---------------recessive trait