exam 3 Flashcards
codominance
spotted chicken
incomplete dominance
mixture of colors chicken
X-inactivation:
occurs in both XX and XXY
results in formation of Barr body
leads to dosage compensation for the X chromosomes
produces a mosaic phenotype in XX
X inactivation does not:
occur for both the sex chromosomes and autosomes
pleitrophy
one gene has multiple effects on the phenotype
hemizygous
an XY individual expressing the gene on the X chromosome
polygenic
many genes affect single character
homozygous
an individual with this genotype produces one type of gamete
epistasis
one gene influences the expression of another
heterozygous
a carrier for a recessive genetic disorder
polygenetic example
more than 50 genes contribute to LDL
pleiotropy example
a single gene can affect LDL, HDL, and triglycerides
epistasis example
multiple genes interact in the same pathway to affect cholesterol level
MAP
add classes being crossed, divide by 100
completely linked genes true:
0 map distance, cannot be separated by crossing over
completely linked genes false:
undergo independent assortment, may or may not be on the same chromosome, recombination frequency is 10%
no specific gender order
multiply and add all possibilities together
specific gender order
one possibility
CF, PKU, sickle cell
recessive
Huntington’s
dominant
hemophilia & R-G color blind
X-linked
type A + B parents = ___ child…
A, B, AB, or O
lab coat/nose color
B= black b=brown
lab pigment
E= yes pigment e= no (yellow)
