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Genetics: Mendelian Freckles are Not a Thing True or False

1. In what inheritance patterns does the genotypic ratio match the phenotypic ratio? -> Codominance and incomplete dominance
2. Alleles are different _______ of a gene. -> fragments
3. The presence of freckles is a dominant Mendelian trait in humans. If your cousin has freckles, but her husband doesn’t, what are the chances that their baby will have freckles? -> Either 50% or 100%
4. Hemophilia is an X-linked recessive bleeding disorder. If a normal woman whose father was a hemophiliac marries a normal man, what are the chances of their children having the disease? -> 4/4
5. A cross between a tomato cultivar producing fruit weighing, on average, 4 oz and another producing fruit weighing, on average, 6 oz generates offspring plants bearing fruits that weigh, on average, 8 oz. A possible explanation for this observation could be -> epistatic genetic variance
6. A wild type phenotype -> is the most common phenotype in a population
7. If John’s grandmother on his mother’s side had a mitochondrial disorder, how likely is he to inherit it? -> 0%
8. Mutations in the Rb gene can cause retinoblastoma, a cancer that affects the retina. However, not every individual carrying the disease-causing mutation develops the disease. This phenomenon is known as -> incomplete penetrance
9. In an attempt to reduce the number of bullocks born, which are no use to him for producing milk, a farmer has paid to have his diary herd artificially inseminated with sperm that has had half the sperm carrying a Y chromosome removed. What female-to-male ratio would you expect to see in the calves produced from this procedure? -> 3:1
10. A cat breeder has two Manx cats. What phenotypic ratio of offspring can she expect after mating them together? -> All tailed