Lecture 26 Flashcards
Juvenile Glaucoma
balance of fluid in eyes is disturbed; the pressure on the optic nerve and retinas can lead to blindness; dominant allele that encodes for myocilin protein and can be traced back to a couple in france
Pedigrees
graphs matings and offspring over the years; used to study family history
myocilin
protein found in eye fluid
Dihybrid cross
2 traits are crossed
principle of independent assortment
two genes assort independently from eachother
segregation
Mendel’s first law of heredity
two alleles for a gene segregate during gamete formation and are rejoinde at random (one from each parent) during fertilization
Polygenic inheritance
more than one gene can affect a single trait; results in a continuous distribution (not this or that) in the population; multiple additive contributions to a phenotype by multiple genes
Contiunously varying trait
height, weight, skin color etc
Pleiotropy
a single gene can affect more than one trait (ex cystic fibrosis: affects lungs, liver and pancreas with overproduction of mucus recessive gene)
sickle cell anemia
poor blood circulation; recessive gene
incomplete dominance
heterozygote is intermediate in phenotype (blending of phenotype of dom and recessive)
codominance
when each allele has its own affect on phenotype and some aspect of each is seen in the heterozygote
ABO blood groups
gene encodes for enzyme that attaches markers to cell surface; 3 alleles: A-galactosamine, B-galactose, i- no sugar; A and B are codominant, i is recessive
immune system
can recognize which sugar is on surface of RBC
siamese cat
environment can affect genes; temperature affects which protein is expressed, and phenotypically which color shows up
