Bootcamp Chapter 7 Flashcards
Epistasis
One gene affects the phenotypic expression of a second, separate gene
Pleiotropy
Single gene has more than one phenotypic expression
Polygenic inheritance
The interaction of many genes to shape a single phenotype with continuous variation
X-Inactivation
one of two X chromosomes does not uncoil during embryonic development in female mammals - formation of a Barr body
The unique fur pigmentation of calico cats are the result of
a) linked genes
b) penetrance
c) co-dominance
d) x-inactivation
D
Linked genes are (more likely/less likely) to be separated by recombination during meiosis, and are (less likely/more likely to be) inherited together
less likely, more likely
Mosaicism
Occurs in cells that undergo mitotic nondisjunction during embryonic development - causes a fraction of body cells to have extra or missing chromosomes
What are the gametes of nondisjunction during meiosis I vs. meiosis II?
Meiosis I non disjunction = n+ 1, n+1, n-1, n-1
Meiosis II nondisjunction = n, n, n+1, n-1
Transition Mutation
purine nucleotide is converted to another purine,
or a pyrimidine is converted to another pyrimidine.
Transversion Mutation
purine nucleotide is converted too a pyrimidine nucleotide or vv
Point Mutation
a single nucleotide change causing substitution, insertion, or deletion
Forward Mutation
Wild type allele is changed to a mutant
Turner Syndrome
XO - missing a sex chromosome; results in sterility and physical abnormalities
Klinefelter syndrome
XXY - results in sterility
Edwards Syndrome (Trisomy 18)
characterized by heart defects
Robertsonian Translocation
two different chromosomes breaking and rejoining near the centromeres
If p53 becomes mutated, what will occur?
p53 is the tumor suppressor gene - if this gets mutated then cancer can occur
Where can extranuclear inheritance be found?
mitrochondria and chloroplasts
Huntington’s disease, achondroplasia, and hypercholesterolemia exhibit which inheritance pattern?
a) automosal recessive
b) autosomal dominant
c) x- linked recessive
d) chromosomal
B
PKU, cystic fibrosis, Tay-sachs, sickle cell anemia and galactosemia exhibit which inheritance pattern?
a) automosal recessive
b) autosomal dominant
c) x- linked recessive
d) chromosomal
A
