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9.  The presence or absence of wings on female aphids is a well-known case of polyphenism.  Below are examples of a winged female (right) and of a wingless female (left).   Which one of the following is true of the polyphenism in these adult female aphids?

Extra Credit 2.  The 4 choices below show the genotypes of 4 individuals relative to 4 genes.  The “A gene” and the “B gene” shows complete dominance/recessiveness.  The “R gene” shows incomplete dominance.  The “T gene” is an X-linked gene.  Each gene influences only one trait.      Genotype of individual 1: AA bb R3R4 XTY      Genotype of individual 2: aa Bb R3R5 XTXt      Genotype of individual 3: AA BB R1R1 XTXT      Genotype of individual 4: Aa BB R5R6 XtY Carefully examine these genotypes.  Which of the genes is multiallelic.  Explain your answer.

Extra Credit 1.  Which one of the following best describes the relationship between allele dominance and frequency of the allele in the population?

15.  Which one of the following best describes the product of a gene?

11.  You suspect that a particular phenotype is the result of several genes being expressed together (polygenic inheritance).  You decide to document the occurrence of the phenotype in a population, so you sample about 1,000 people.  Which of the following characteristics are you likely to document if the phenotype is indeed polygenic?  Select all correct choices.

3.  Marine clamworms have flat fleshy appendages used for respiration.  This trait is controlled by a single gene with two alleles.  The alleles display complete dominance/recessiveness.  The dominant allele results in appendages with 3 lobes while the recessive allele results in appendages with 2 lobes. A female worm with 3-lobed appendages mates with a male with 2-lobed appendages.  What is the genotype of the female if some of the offspring have appendages with 2 lobes?

20.  Suppose number of fingers and toes in the North American sasquatch is an X-linked trait represented with the letters A and a.  The dominant allele results in polydactyly, more than 5 fingers on hands and more than 5 toes on feet.  The recessive allele results in “normal” number of fingers and toes, 5 fingers on hands and 5 toes on feet.  Which of the following genotypes would result in a sasquatch with the normal number of fingers and toes?  Select all correct choices.

10.  Red-headedness in humans is due to a recessive allele of the MC1R gene.  Geneticists know that the MC1R gene in humans displays epistasis.  What does this tell you about the expression of the MC1R gene in the phenotype?

6.  Examine the human karyotype below and answer the associated questions.        a.  Does this karyotype indicate a male or a female human?  How do you know?      b.  Name the syndrome associated with the non-disjunction aneuploidy shown in the karyotype.      c.  Which one of the following correctly describes the “source” of this aneuploidy:                Non-disjunction that could only have occurred during oogenesis.                Non-disjunction that could only have occurred during spermatogenesis.                Non-disjunction that could have occurred during oogenesis or occurred during spermatogenesis.

1.  Which one of the following choices correctly diagrams the Central Dogma of Biology?