Some Dogs Have Erect Ears; Others Have Drooping Ears

question 71

Multiple Choice

Some dogs have erect ears; others have drooping ears. Some dogs bark when following a scent; others are silent. Erect ears and barking are due to dominant alleles located on different chromosomes. A dog homozygous for both dominant traits is mated to a droopy-eared, silent follower. The phenotypic ratio expected in the F ₁ is

• A) 9:3:3:1.
• B) 100 percent of one phenotype.
• C) 1:1.
• D) 1:2:1.
• E) 3:1.

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