Bio 160 Lab Test 2 Online Questions Study Guide Questions And Correct Answers

A genetic cross of inbred snapdragons with red flowers with inbred snapdragons with white flowers resulted in F1-hybrid offspring that all had pink flowers. When the F1 plants were self-pollinated, the resulting F2-generation plants had a phenotypic ratio of 1 red: 2 pink: 1 white. The most likely explanation is: {Ans: heterozygous plants have a different phenotype than either inbred parent because of incomplete dominance of the dominant allele. The features of crosses involving incomplete dominance are intermediate phenotype of heterozygous individuals, and parental phenotypes reappear in F2 when heterozygotes are crossed.}Manx cats are heterozygous for a dominant mutation that results in no tails (or very short tails), large hind legs, and a distinctive gait. The mating of two Manx cats yields two Manx kittens for each normal, long-tailed kitten, rather than three-to-one as would be predicted from Mendelian genetics. Therefore, the mutation causing the Manx cat phenotype is likely a(n) __________ allele. {Ans: lethal The predicted segregation pattern in the F2 generation is 1/4 normal (homozygous), 1/2 Manx phenotype (heterozygous), an 1/4 embryonic lethal (homozygous for the Manx allele)}In Mendel's experiments, the spherical seed character (SS) is completely dominant over the dented seed character (ss). If the