MBG 2400 Exam Review questions well
answered to pass
Polymorphism - correct answer ✔✔the presence of genetic variation within a population, upon
which natural selection can operate
What are B and B in an organism's DNA? - correct answer ✔✔Represent a difference (allele or
polymorphism) in the DNA sequence at a location (locus) in the organisms genome. The dual
strand composition makes it convenient to use letters of the alphabet and capitalize one.
3 factors affecting independence and F2 ratios - correct answer ✔✔Pleiotropy, epistasis, linkage
Pleiotropy - correct answer ✔✔one locus affects two or more traits
Epistasis - correct answer ✔✔alleles at one locus affect the expression of alleles at a different
locus
Linkage - correct answer ✔✔two or more loci are on the same chromosome
How does W dominant allele for white cat also cause deafness? - correct answer
✔✔Melanocytes
- produce fur pigmentation but are also present for electrical transmission to the brain
- defective melanocyte development means no pigment or electrical signals = white and deaf
How does W allele for white cat display epistasis? - correct answer ✔✔W masks all other colour
and pattern genes and therefore shows dominant epistasis, ww allows expression of colours and
patterns
, Calculating allele frequencies by counting - correct answer ✔✔separate genotypes into how
many A and a alleles for each, add up for each and divide by total # alleles
OR
p = P + 0.5H
q = Q + 0.5H
and P + H + Q = 1
where P is freq of homo dominant, H is freq of hetero and Q is freq of homo recessive
Hardy-Weinberg Equilibrium - correct answer ✔✔Present in a large, random mating population
in the absence of migration, mutation and selection
"Allele frequencies and genotypic frequencies remain constant and genotypic frequencies are
determined by allele frequencies"
What does it mean to say that Hardy Weinberg Equilibrium is a utopian state? - correct answer
✔✔Most populations break some or all of the rules
Do p and q change with random mating? - correct answer ✔✔No
What are you assuming by estimating q based on the frequency of homozygous recessive
genotypes in the population? - correct answer ✔✔Assuming hardy weinberg and and ignoring
the contribution to q of the heterozygotes
*use f(aa) to estimate f(a) only if f(Aa) is not available*
answered to pass
Polymorphism - correct answer ✔✔the presence of genetic variation within a population, upon
which natural selection can operate
What are B and B in an organism's DNA? - correct answer ✔✔Represent a difference (allele or
polymorphism) in the DNA sequence at a location (locus) in the organisms genome. The dual
strand composition makes it convenient to use letters of the alphabet and capitalize one.
3 factors affecting independence and F2 ratios - correct answer ✔✔Pleiotropy, epistasis, linkage
Pleiotropy - correct answer ✔✔one locus affects two or more traits
Epistasis - correct answer ✔✔alleles at one locus affect the expression of alleles at a different
locus
Linkage - correct answer ✔✔two or more loci are on the same chromosome
How does W dominant allele for white cat also cause deafness? - correct answer
✔✔Melanocytes
- produce fur pigmentation but are also present for electrical transmission to the brain
- defective melanocyte development means no pigment or electrical signals = white and deaf
How does W allele for white cat display epistasis? - correct answer ✔✔W masks all other colour
and pattern genes and therefore shows dominant epistasis, ww allows expression of colours and
patterns
, Calculating allele frequencies by counting - correct answer ✔✔separate genotypes into how
many A and a alleles for each, add up for each and divide by total # alleles
OR
p = P + 0.5H
q = Q + 0.5H
and P + H + Q = 1
where P is freq of homo dominant, H is freq of hetero and Q is freq of homo recessive
Hardy-Weinberg Equilibrium - correct answer ✔✔Present in a large, random mating population
in the absence of migration, mutation and selection
"Allele frequencies and genotypic frequencies remain constant and genotypic frequencies are
determined by allele frequencies"
What does it mean to say that Hardy Weinberg Equilibrium is a utopian state? - correct answer
✔✔Most populations break some or all of the rules
Do p and q change with random mating? - correct answer ✔✔No
What are you assuming by estimating q based on the frequency of homozygous recessive
genotypes in the population? - correct answer ✔✔Assuming hardy weinberg and and ignoring
the contribution to q of the heterozygotes
*use f(aa) to estimate f(a) only if f(Aa) is not available*
