3. Extensions to Mendelian Inheritance

Which of the following gametes cannot be formed from the genotype AaBBCc?

Which of the following gametes cannot be formed from the genotype DDeeFfGG?

Which of the following gametes cannot be formed from the genotype HhJjKK?

A pure-breeding tall plant producing oval fruit as described in Problem 2 is crossed to a pure-breeding short plant producing round fruit.

If the F₁ identified in part (a) are crossed to one another, what proportion of the F₂ are expected to be short and produce round fruit? What proportion are expected to be tall and produce round fruit?

A pure-breeding tall plant producing oval fruit as described in Problem 2 is crossed to a pure-breeding short plant producing round fruit.

The F₁ are crossed to short plants producing oval fruit. What are the expected proportions of progeny phenotypes?

In tomato plants, purple leaf color is controlled by a dominant allele A, and green leaf by a recessive allele a. At another locus, hairy leaf H is dominant to hairless leaf h. The genes for leaf color and leaf texture are separated by 16 m.u. on chromosome 5. On chromosome 4, a gene controlling leaf shape has two alleles: a dominant allele C that produces cut-leaf shape and a recessive allele c that produces potato-shaped leaf.

Fully explain the number and frequency of each phenotype class.

In tomato plants, purple leaf color is controlled by a dominant allele A, and green leaf by a recessive allele a. At another locus, hairy leaf H is dominant to hairless leaf h. The genes for leaf color and leaf texture are separated by 16 m.u. on chromosome 5. On chromosome 4, a gene controlling leaf shape has two alleles: a dominant allele C that produces cut-leaf shape and a recessive allele c that produces potato-shaped leaf.

The cross of a purple, hairy, cut plant heterozygous at each gene to a green, hairless, potato plant produces the following progeny:

        Phenotype             Frequency %   _
  Purple, hairy, cut                21
  Purple, hairy, potato           21
  Green, hairless, cut            21
  Green, hairless, potato       21
  Purple, hairless, cut            4
  Purple, hairless, potato.      4
  Green, hairy, cut                  4
  Green, hairy, potato.            4  _
                                             100
Give the genotypes of parental and progeny plants in this experiment.