BLG 144 MIDTERM LATEST EXAM ALL QUESTIONS
AND ANSWERS SURE A+
✔✔darwin's 4 postulates - ✔✔1.individual organisms that make up a population vary in
traits they possess
2. some of the trait differences are heritable;passed on to their offspring genetically
3. many more offspring are produced than can possibly survive
4. individuals that survive best and produce more offspring is not random; those with
certain heritable traits are more likely to survive and reproduce
✔✔fitness - ✔✔ability for an organism to produce surviving offspring
✔✔adaption - ✔✔heritable trait that increases the fitness of an individual in a particular
environment relative to individuals lacking that trait
✔✔polygenic - ✔✔many genes influencing one trait
✔✔true or false:
during natural selection, individuals do not change, but the population does - ✔✔true;
natural selection acts on individuals but it is the populations that evolve
✔✔what are key questions to ask to see if darwin's postulates work for a certain
organism - ✔✔1. was there reproductive success
, 2. did variation exist in the population
3. is the variation heritable
4. did selection occur
✔✔natural selection - ✔✔when organisms are better adapted to their environment, they
tend to survive and reproduce.
-leads to a change in characteristics of the population
-sorts existing variants, it does not change them
✔✔acclimation - ✔✔occurs when an individual's phenotype change in environment but
genotypes remained fixed
-physiological adaptations that occur through experimentally induced stressors (ex.
arctic fox changes in fur color by season under temperature control)
-NOT A GENETIC CHANGE
✔✔true or false: evolution isn't about being better, it's about becoming better suited and
adapted to the environment - ✔✔true
✔✔what is true about individuals with selfish, cheater alleles - ✔✔-they survive and
produce offspring more likely than individuals with self-sacrificing alleles
✔✔genetic correlation - ✔✔occur because of pleiotropy (single allele affects many
traits)
-lack of genetic variation is important
✔✔fitness trade-off - ✔✔compromise of traits - how traits perform in the environment
✔✔what are 4 evolutionary processes responsible in evolution - ✔✔1. natural selection:
increase frequency of alleles
2. mutation: modifies allele frequencies by introducing new alleles
3. gene flow: individuals leave one area, reproduce, and introduces new genes
4. genetic drift: causes allele frequencies to change randomly
✔✔gene pool - ✔✔all gametes produced in population
✔✔hardy- weinberg principle - ✔✔determines genotypes present in next generation
p + q = 1 ---- allele frequencies
p^2 +2pq+ q^2 = 1 ----- genotype frequencies
✔✔what conditions must be met for the hardy-weinberg principle to occur - ✔✔1.
random mating
2. no mutation
3. no gene flow
4. no genetic drift/random allele frequency change
AND ANSWERS SURE A+
✔✔darwin's 4 postulates - ✔✔1.individual organisms that make up a population vary in
traits they possess
2. some of the trait differences are heritable;passed on to their offspring genetically
3. many more offspring are produced than can possibly survive
4. individuals that survive best and produce more offspring is not random; those with
certain heritable traits are more likely to survive and reproduce
✔✔fitness - ✔✔ability for an organism to produce surviving offspring
✔✔adaption - ✔✔heritable trait that increases the fitness of an individual in a particular
environment relative to individuals lacking that trait
✔✔polygenic - ✔✔many genes influencing one trait
✔✔true or false:
during natural selection, individuals do not change, but the population does - ✔✔true;
natural selection acts on individuals but it is the populations that evolve
✔✔what are key questions to ask to see if darwin's postulates work for a certain
organism - ✔✔1. was there reproductive success
, 2. did variation exist in the population
3. is the variation heritable
4. did selection occur
✔✔natural selection - ✔✔when organisms are better adapted to their environment, they
tend to survive and reproduce.
-leads to a change in characteristics of the population
-sorts existing variants, it does not change them
✔✔acclimation - ✔✔occurs when an individual's phenotype change in environment but
genotypes remained fixed
-physiological adaptations that occur through experimentally induced stressors (ex.
arctic fox changes in fur color by season under temperature control)
-NOT A GENETIC CHANGE
✔✔true or false: evolution isn't about being better, it's about becoming better suited and
adapted to the environment - ✔✔true
✔✔what is true about individuals with selfish, cheater alleles - ✔✔-they survive and
produce offspring more likely than individuals with self-sacrificing alleles
✔✔genetic correlation - ✔✔occur because of pleiotropy (single allele affects many
traits)
-lack of genetic variation is important
✔✔fitness trade-off - ✔✔compromise of traits - how traits perform in the environment
✔✔what are 4 evolutionary processes responsible in evolution - ✔✔1. natural selection:
increase frequency of alleles
2. mutation: modifies allele frequencies by introducing new alleles
3. gene flow: individuals leave one area, reproduce, and introduces new genes
4. genetic drift: causes allele frequencies to change randomly
✔✔gene pool - ✔✔all gametes produced in population
✔✔hardy- weinberg principle - ✔✔determines genotypes present in next generation
p + q = 1 ---- allele frequencies
p^2 +2pq+ q^2 = 1 ----- genotype frequencies
✔✔what conditions must be met for the hardy-weinberg principle to occur - ✔✔1.
random mating
2. no mutation
3. no gene flow
4. no genetic drift/random allele frequency change
