QUIZ 1. In the Punnett square analysis of two parents that each have a dominant (T) allele and recessive (t) allele: what is the ratio of dominant to recessive phenotypes of offspring having the trait? a. 1:2 b. 3:1 c. 1:3 d. 1:2 Answer: b. The ratio of dominant to recessive traits is 3:1 when using the Punnett square with three times as many dominant traits as recessive traits seen in the offspring. 2. In the Punnett square analysis of two parents that have a dominant T allele and a recessive t allele, what is the ratio of homozygous dominant to homozygous recessive genotypes in the offspring? a. 1:1 b. 3:1 c. 1:3 d. 1:2 Answer: a. The ratio of homozygous dominant and homozygous recessive traits is 1:1 with the entire ratio of all genotypes being 1:2:1, with the ratio representing homozygous dominant: 2 heterozygous: homozygous recessive. 3. What is it called when a trait is equally expressed in the offspring of the male and female animal? a. Autosomal dominant b. Codominance c. X-linked recessive d. Autosomal recessive
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