SOLVED

31. In what kind of classic Mendelian cross would you expect to find a ratio of 9:3:3:1 among the F2 offspring? A. monohybrid cross B. dihybrid cross C. testcross D. None of the choices is correct. 32. If a woman is a carrier for the color-blind recessive allele and her husband is normal, what are their chances that a son will be color-blind? A. None since the father is normal. B. 50% since the mother is the only carrier. C. 100% because the mother has the gene. D. 25% because the mother is a hybrid. E. None since he will also be just a carrier. 33. In pea plants, the gene for round seed (R) is dominant, and wrinkled seeds (r) are recessive. The endosperm of the pea is also either starchy, a dominant gene (S), or waxy (s). What can be said of a fully heterozygous, dihybrid cross? A. It is impossible to secure offspring that are homozygous for both dominant genes. B. It is impossible to secure offspring that are homozygous for both recessive genes. C. It is impossible to secure offspring that are homozygous for one dominant gene such as round seed and homozygous recessive for the other recessive waxy gene. D. All of these choices are impossible combinations in a dihybrid cross. E. All of these choices are possible combinations in a dihybrid cross. 34. A testcross involves an individual exhibiting the dominant phenotype but an unknown genotype being crossed with an individual that has a(n) ___________ genotype. A. homozygous dominant B. heterozygous dominant C. homozygous recessive D. any of the choices 35. If individuals exhibiting a dominant phenotype are crossed and produce only offspring with the dominant phenotype, what would be the logical genotype of the parents? A. both are homozygous recessive B. one is heterozygous and one is homozygous dominant C. both are homozygous dominant D. both are heterozygous E. two of the options may be correct  Â