1 .		Alleles are alternate forms of a gene. The alleles for the gene that determines blood type in humans are found at _______. (Level 1) [Hint]
2 .		Humans have about 100,000 genes. How many alleles of each of these genes are present in your muscle cells, disregarding genes on the X and Y chromosomes? (Level 1) [Hint]
3 .		If a plant is true-breeding for a flower color, it is _______ for the flower-color gene. (Level 1) [Hint]
4 .		A Punnett square is _______. (Level 1) [Hint]
5 .		If a gene has alleles that are incompletely dominant, an individual that is heterozygous at this locus will have characteristics that are _______. (Level 1) [Hint]
6 .		Which of the following statements is true? (For extra practice, try to change the incorrect answer to make it a correct statement. Also, give an example for each of the correct statements.) (Level 1) [Hint]
7 .		Cystic fibrosis is a recessive trait. Imagine that your friend Roger has cystic fibrosis but that his parents do not. What do you know about Roger's alleles and those of his parents at the cystic fibrosis locus of their DNA? (Level 2) [Hint]
8 .		Anne Boleyn, King Henry VIII's second wife, was beheaded because she did not provide him with a son as an heir. Explain why King Henry should have blamed himself and not his wife. (Level 2) [Hint]
9 .		In many cases, conditions that occur more frequently in males than in females are due to sex-linked inheritance. Male pattern baldness is more common in males than in females, but that is not because of sex-linked inheritance. Suggest a possible explanation. (Level 2) [Hint]
10 .		A couple brings home their new, nonidentical twin daughters, Joan and Jill. After several months, the father begins to suspect that there was a mix-up at the hospital, because Jill doesn’t look much like either parent or like her sister. When the twins' blood tests come back, the father calls his lawyer to start a lawsuit against the hospital. The mother, father, and Joan have type A blood, but Jill has type O blood. Does the father have a case? Explain your answer. (The gene for blood type has three alleles: A, B, and O. The A and B alleles are codominant, and the O allele is recessive.) (Level 3) [Hint]
11 .		What are alleles? [Hint]
12 .		Consider this hypothetical example: If you were to apply Mendel's reasoning to the past presidential election, and hanging chads (C) were dominant to pregnant chads (c), which of the following genotypes would result in the expression of the dominant phenotype from a cross of F1 offspring that are Cc? [Hint]
13 .		What does Mendel's law of independent assortment tell us about the behavior of genes during meiosis? [Hint]
14 .		If an organism has only three chromosomes, how many chromosomes are autosomes? [Hint]
15 .		A single gene capable of influencing multiple phenotypes within a single phenotype is said to be _______. [Hint]
16 .		What is the root cause of sickle-cell anemia? [Hint]
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