Non-Mendalian Punnet Squares 3.2 U3 Flashcards
What is incomplete dominance?
One allele is not completely dominant over another
Result = a different phenotype, a sort of “blend”!
RW
C^RC^W
RR’
What is Codominance?
BOTH phenotypes are clearly expressed
(human blood types demonstrate codominance!)
Result = both traits clearly visible together, stripes/spots/multiple proteins/etc.
RW
C^RC^W
RR’
What is multiple alleles? Ex
A gene that has more than just two alleles
Ex. There are three alleles for human blood type (A, B, & O)
So, human blood type exhibits codominance and multiple alleles!
Explain Human Blood Type and how the Antigens Work?
Red blood cells carry antigens which trigger an immune response. There are two types of antigens, A and B.
People with type A blood have the A antigen, type B people have the B antigen, type AB have both, and type O have neither.
Both A antigens and B antigens are clearly expressed and are written IA and IB while having no antigens is written i.
What is the + and - on blood types?
There are also “+” vs. “-” blood types!
Rh is just another antigen on RBCs!
What is Sex-Linked Inheritance?
A gene for a trait is found on the X or Y chromosomes
Genes on Y - only found in males
Recessive alleles found only on X - trait is more likely in males
*assuming XX vs XY chromosomes, and not any other combinations!**
Understand Sex-Linked Inheritance Punnet Squares :(
What is a polygenic trait?
A trait is controlled by two or more genes.
Often results in a range/spectrum of phenotypes!!
Ex: height, skin color, eye color
What is mitochondrial inheritance?
In humans all (or nearly all) of our mitochondria come from the cytoplasm of the ovum (egg cell)!
Thus, offspring typically have identical mitochondrial DNA to their mother!
What are the things that effect your genotype? EX
Environmental conditions can affect gene expression!
Phenotype depends on genes + environment
SIAMESE CAT WITH TEMPERATUR SENSITIVE
