Unit 5 Worksheet 3

Genetics

  1. Define:

Genotype –

Phenotype –

Locus –

Homozygous –

Heterozygous –

  1. Which progeny are homozygous and which are heterozygous?
  1. A man has six fingers on each hand and six toes on each foot. His wife and their daughters have the normal number of digits. Having extra digits (“polydactyly”) is conferred by a dominant allele. What percent of this couple’s children would be expected to have extra digits?
  1. What is a dihybrid cross?
  1. Are genes inherited independently or dependently according to Mendel?
  1. In regards to the question above, what was Mendel missing?
  1. You are given a pea plant that is tall with axial flowers. You wish to determine if this plant is a homozygote or a heterozygote. What is the phenotype of the pea plant that you will have to cross this unknown with in order to discover its genotype?
  1. Tall, terminal
  2. Tall, axial
  3. Dwarf, terminal
  4. Dwarf, axial
  1. Incomplete dominance: define and give an example.
  1. Why are there four different blood types when there is only IA, IB, and i?
  1. A woman with type A blood whose mother had type O blood marries a man with type B blood whose mother also had type O blood. Draw a Punnett square indicating the types of gametes both the man and the woman can produce and the possible offspring they could have. What is the probability that they will have a child with type O blood?
  1. Define pleiotropy and give an example.
  1. Define polygenetic inheritance and give an example.
  1. Phenotype is effected by the genotype AND
  1. Two parents have a child. One parent is heterozygous for the trait, and one has blonde hair. Blonde hair color is a recessive trait. What is the probability that their child will have blonde hair? What is the probability that their child will be a carrier for blonde hair? (hint: Punnett square!)
  1. In turtles, (pretend that) smooth shells are dominant over bumpy shells. If one parent turtle is heterozygous and all of the offspring have smooth shells, what was the genotype of the other parent? What was the phenotype of the other parent? (hint: Punnett square!)
  1. Cystic Fibrosis

NN / Nn (carrier)
Nn (carrier) / nn (CF)

With the outcome above, what were the alleles of both parents?

____ % chance their child would be a carrier.

____% chance their child would have Cystic Fibrosis.

____% chance their child wouldn’t be a carrier or have Cystic Fibrosis.

  1. A flower’s gene for red color is dominant (R) over it’s allele for white flower color (r). If one parent is heterozygous and all of the offspring produce red flowers, what is the genotype of the other parent?