A tall pea plant is crossed with a recessive dwarf pea plant. What will the phenotypic and genotypic ratio of offspring be

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• A tall pea plant is crossed with a recessive
  dwarf pea plant. What will the phenotypic and
  genotypic ratio of offspring be
• a. if the tall plant was TT?
• b. if the tall plant was Tt?
• 2. A true-breeding tall, purple-flowered pea
  plant (TTPP) is crossed with a true-breeding
  dwarf, white flowered plant (ttpp).
• a. What is the phenotype of the F1 generation?
• b. What is the genotype of the F1 generation?
• c. What four types of gametes are formed by the
  F1 plants?
• d. Create and solve a punnett square to show the
  offspring of the F2 generation.
• d. List the phenotypes and ratios found in the
  F2 generation.

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• 3. In the following cross, what is the
  probability of obtaining offspring that show all
  three dominant traits, A_B_C_ ( _ indicates that
  the second allele can be either dominant or
  recessive without affecting the phenotype
  determined by the first dominant allele)?
• AaBbcc x AabbCC
• a. probability of offspring that are A_B_C_ ?
• b. What is the probability that the offspring
  of this AaBbcc x AabbCC cross will show at least
  two dominant traits?

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• 5. A dominant allele M is necessary for the
  production of the black pigment melanin, mm
  individuals are white. A dominant allele B
  results in the deposition of the a lot of pigment
  in an animals hair, producing a black color. The
  genotype bb produces brown hair. Two black
  animals heterozygous for both genes are bred.
  Using MmBb x MmBb
• a. List the three phenotypes and possible
  genotypes
• b. List the ratios for each of the three
  phenotypes.
• Phenotype Genotype Ratio

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Linked Genes

• Given b gray vg normal wings
• b black vg vestigial
  wings
• Cross (Male) b b vg vg X (Female) b b vg
  vg
• Mendels law of independent assortment would
  produce which phenotypes?
• The actual results pg.280

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• 6. Determine the sequence of genes along a
  chromosome based on the following recombination
  frequencies
• A-B, 8 map units
• A-C, 28 map units
• A-D, 25 map units
• B-C, 20 map units
• B-D, 33 map units

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• 7. A man with hemophilia (a recessive, sex linked
  condition) has a daughter of normal phenotype.
  She marries a man who is normal for the trait.
• What is the probability that a daughter of this
  mating will be a hemophiliac?
• That a son will be hemophiliac?
• If the couple has four sons, what is the
  probability that all four will be born with
  hemophilia?

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• 8. Red-green colorblindness is caused by a SL
  recessive allele. A CB man marries a woman with
  normal vision whose father was CB. What is the
  probability of having a daughter who is also CB?
  What is the probability that their first son will
  be CB?
• 9. A wild-type fruit fly (heterozygous for gray
  body color and normal wings) is mated with a
  black fly with vestigial wings. The offspring
  have the following phenotypic distribution wild
  type 778, black vestigial 785, black normal 158,
  gray vestigial 162. What is the recombination
  frequency between these genes for body color and
  wing size?