Unit 9 Flashcards
What is intermediate pattern
When the heterozygous genotype is a homogenous blend of the two phenotypes
What is codominance
When there is no dominant allele, the heterozygous genotype shows both phenotypes
What is multiple allele
There are more than 2 alleles in the gene pool for one trait
What is polygenic traits
Two or more genes control one trait
What is pleiotropy
One gene controls many traits
What is epistasis
Two genes are involved where the one controls the expression of the other
What does autosomal mean
Its not sex-linked
What are two characteristics of polygenic inheritance
The traits show continuous variation and are referred to as quantitative traits
What is the epistasis in Labrador retreivers
-gene 1 determines if pigment can be made, has two alleles where pigment deposition is dominant
-gene 2 determines color, where black is dominant over brown
What ratio does epistasis create
A 9:3:4 ratio
What is the environmental effect on phenotypes
Some alleles only allow pigment under a certain temperature, ex: himalayen cats