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Answer your essay choice for SECTION B here

GRAND TOTAL: 150 MARKS   Have you answered THREE questions..? 1  x Section A Source-Based Question 1 x Section B Essay Question 1 x Section A OR Section B Question

Answer SECTION B here (optional second choice)

19.  Match the statement with the correct chromosomal alteration to which it applies.

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?

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.

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

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?