WITH 160+ EXPERT CERTIFIED QUESTIONS
AND ANSWERS I ALREADY GRADED A+
what are two factors that contribute to phenotype? - Answergenotype and
environment
species - Answerindividuals that are able to exchange genetic material
gene pool - Answerall alleles present in individuals of that species
populations - Answerinterbreeding groups of organisms of the same species living in
the same geographical area
what are two main sources that lead to genetic variation? - Answermutation and
recombination
what can somatic mutations lead to? - Answercancer, disease and even death to an
INDIVIDUAL
what can germ line mutations lead to? - Answermutations that are passed down to
offspring
recombination; name two ways it can occur - Answernew alleles may be generated
through crossing over and independent assortment
allele frequency - Answerrate of occurrences of alleles in a population
gene locus - Answerthe location of a certain gene/allele
allele - Answera form of a gene; one copy of a gene
example: A, a
how is genetic variation measured? - Answerthrough the allele frequency equation
what is the allele frequency equation? - AnswerAF=(# of copies of an allele)/(total # of
alleles in population)
evolution - Answerchange in allele frequency or genotype frequency over time
, how is evolution measured? - Answerexaminable physical traits, gel electrophoresis,
DNA sequences;
most importantly: the hardy-weinberg equilibrium
what does the hardy-weinberg equilibrium model describe? - Answerthe situation in
which evolution does NOT occur
a population in the HW equilibrium meets what requirements? - Answer1. closed
population (no migration or gene flow)
2. no mutations
3. large population (no genetic drift)
4. random mating (no sexual selection)
5. no natural selection
what is the HW equation? - Answerp^2 + 2pq + q^2
natural selection occurs when... - Answer...individuals with certain traits reproduce
more offspring than do individuals without those traits
stabilizing selection - Answeragainst the extremes
directional selection - Answeragainst one extreme
disruptive selection - Answeragainst the mean
STRONG and QUICK
artificial selection - Answerselection by breeder rather than competition
positive selection - Answerselection that increases the frequency of a FAVORABLE
allele
negative selection - Answerselection that decreases the frequency of a deleterious
allele
balancing selection - Answerrefers to when two allele are maintained in the
population
ex: malaria and the heterozygote advantage (heterozygote's fitness is higher than either
homozygotes resulting in selection that ensures both alleles to remain in the population)
sexual selection - Answerpromotes traits that increase an individuals access to
reproductive opportunities