#28. Which of the following scenarios best describes an epistatic gene?Select one:a). Fur pattern is controlled by two genes such that one gene inhibits the expression of the other gene.b). Individuals with sickle cell anemia and carriers of the sickle cell allele have some resistance to malaria.c). Mouse fur colours are expressed as a blend of the dominant black colour and the recessive white colour, resulting in a heterozygous brown colour.d). Chicken combs follow a dominance hierarchy whereby a walnut comb is the most dominant and a single comb is the least dominant.
#29.Which of the following statements does NOT describe an environmental influence on the expression of a gene?Select one:a). More than a single gene is involved in the expression of human height, weight, and skin colour.b). Colder incubation temperatures of gecko eggs yield more females and warmer temperatures yield more males.c). Siamese cats have darkened paws, nose, and tip of tail due to a gene that allows their skin and fur to darken in the parts of their bodies that need to retain more heat, their extremities.d). Exposure to sunlight increases melanin production in human skin.
#30.Melanin is a skin pigmentation that absorbs and dissipates broadband UV rays. Since UV radiation causes DNA damage, melanin pigments protect the skin and reduce the risk of cancer. When skin is exposed to sunlight, melanin production is increased, causing the skin to tan. This demonstrates that... Select one:a). the expression of some genes is influenced by the environment.b). the environment causes mutations that increase the chance of survival.c). the environment causes mutations that have a large effect on the chance of survival.d). the environment causes mutations that have no effect on the chance of survival.
#31. In corn plants, a dominant allele (K) allows kernel colour and a recessive allele (k) inhibits kernel colour when homozygous. On a different chromosome, the dominant gene P causes purple kernel colour and the homozygous recessive genotype causes red kernel colour.
A true breeding white corn plant was crossed with a purple corn plant, yielding 50% red corn plants and 50% purple corn plants.
What are the genotypes of the parental corn plants?Select one:a). KkPP cross timeskkPP. b). KKPp cross times kkpp.c). KKPP cross timeskkPp.d). kkPp cross timesKkPp
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