Pedigree practice

    Interactive tutorial:


  1. See the pedugree at right showing cystic fibrosis inheritance. The individual labeled "4" in generation III is
    1. a healthy male. (wrong)
    2. a healthy female. <==== correct
    3. a male with cystic fibrosis. (wrong)
    4. a female with cystic fibrosis. (wrong)
    5. one of the parents. (wrong)

  2. In this pedigree, the shaded individuals are homozygous recessive. What is the genotype of individual B?
    1. heterozygous <==== correct
    2. homozygous recessive (wrong)
    3. homozygous dominant (wrong)
    4. none of the above (wrong)
    5. can not tell from the diagram (wrong)

  3. What is the genotype of individual E?
    1. heterozygous <==== correct
    2. homozygous recessive (wrong)
    3. homozygous dominant (wrong)
    4. none of the above (wrong)
    5. can not tell from the diagram (wrong)

  4. If E married an individual who is homozygous recessive, what is the probability that their first child will be homozygous recessive?
    1. 1/8 (wrong)
    2. 1/4 (wrong)
    3. 1/2 <==== correct
    4. 1 (wrong)
    5. 0 (wrong)