Results in an equal expression of two alleles. (i.e. White spotted red flowers)
What is over dominance?
Two different alleles that produce proteins with slightly different amino acid sequences. Which allows an individual to function over broader range of conditions or become less susceptible to illnesses.
What are two examples of overdominance? (describe each)
Cystic fibrosis : carriers are more resistant to water loss illnesses.
PKU : embryos are more resistant to miscarriages due to fungal toxins.
What is hybrid vigor?
Hybrids display traits superior to other non hybrids due to multiple alleles.
Most is due to intraspecific crossing of sub-species, varieties, breeds, strains, or populations.
What is Incomplete pentrance? (Give an example)
Phenomenon in which a dominate allele does not always penetrate into the phenotype of the individual. At the population level 60% show the dominate trait in heterozygous individuals.
Polydactyly ( extra fingers and toes)
What does it mean to have sex influenced inheritance? (Give an example)
An allele can be dominant in one sex and recessice in the other.
Baldness : Autosomal trait (chromosome 4)
What is a sex limited trait?
A trait that only occurs in one of the sexes.
Occurs on the sex chromosome.
What is gene interaction?
Expression of a phenotypic trait is the result of the expression of many different interacting genes.
Give an example of Gene interaction.
Glucose metabolism. This requires the production of various enzymes to complete, each having their own gene.
What is epistasis?
An example of gene interaction.
Alleles of one gene mask the phenotypic effects of the alleles of another gene.
Can have two or more genes coding for different protiens in an enzymatic pathway producing a single product. (Flower pigment color)