In humans, two recessive alleles results in sickle-shaped blood cells, leading to sickle cell anemia. Two dominant alleles results in normal blood cells. People who are heterozygous have a blended phenotype:
they have slightly twisted blood cells that are resistant to malaria.
NN = normal blood cells
Nn = slightly twisted blood cells, which are resistant to malaria
nn = sickle shaped blood cells, leading to sickle cell anemia
Is this an example of incomplete dominance or codominance? (Circle one.)
A person who has sickle cell and a person with normal blood cells have children. Draw a Punnett Square
to represent this cross.
What fraction (or percent) of their children will most likely be resistant to malaria?
What fraction (or percent) of their children will most likely have sickle cell anemia?
What fraction (or percent) of their children will most likely have normal blood cells?