BIO 320 EXAM 2 QUESTIONS AND
ANSWERS 100% SOLVED.
What is a good definition of evolution? Does the theory of evolution include evolutionary
processes or evolutionary relationships (or both)? - ANSWERdescent with modification-
a change in allele frequencies or genetic makeup over time
What does it mean to say that evolution is a 'theory'? - ANSWERthere are lots of
different hypotheses for how evolution occurred, some have more support than others
gene - ANSWERhereditary determinant (sequence of DNA)for a trait
alleles - ANSWERdifferent versions of the same gene
genotype - ANSWERalleles found in a particular individual
phenotype - ANSWERexpressed trait of an individual
What is heritability? Why is heritability important for the process of evolution? -
ANSWERthe proportion of total phenotypic variation in a trait attributable to genetic
variation(and therefore can be passed on to offspring)
heritability equation - ANSWERℎ2 = 𝑉𝑃/𝑉𝐺
ℎ2 = 𝑉𝐺/𝑉𝐺+𝑉𝐸
VP: phenotypic variance
VG: genetic variance
VE: environmental variance
What are polygenic traits? What is pleiotropy? - ANSWERpolygenic traits are two or
more genes and interactions which vary along a continuum
pleiotropy: genes that affect more than one trait
What is plasticity? What is acclimation? Why are these processes not considered to be
evolutionary? - ANSWERplasticity: variation among individuals in form and function as a
result of environmental influences
acclimation: adjustment to change in a particular environmental factor
they are not genetic adaptations
Who are the two founders of the theory of evolution by natural selection? -
ANSWERcharles darwin and alfred russel wallace
, On what timescales do evolutionary processes occur? How do they compare to
ecological timescales? - ANSWER
What are the various lines of evidence we have that supports the theory of evolution? -
ANSWER-DNA analyses demonstrate that all of life has had a common origin
-fossil record depicts species changing throughout geological strata
-we can observe it taking place
-we can force evolution to take place
What is biological fitness? What are the two components that are often used to try to
quantify or understand biological fitness? - ANSWERthe ability of an organism to
survive AND/OR reproduce
leads to adaptive evolution
What are the three requirements for evolution by natural selection to be possible? -
ANSWER1. variation
2. heritability
3. differential fitness
What is an adaptation?
Can you understand an adaptation by considering an organism alone (without
consideration of the environment)? - ANSWERan adaptation is an inherited trait of an
organism that enhances its biological fitness
no, because adaptations consider the survival and/or reproduction in a certain
environment
What is artificial selection? What is sexual selection? How do they compare and
contrast to natural selection? - ANSWERsexual selection: form of natural selection in
which individuals with certain traits are more likely to obtain mates
artificial selection: humans modifying organisms over many generations
What are the differences between directional, disruptive, and stabilizing selection? -
ANSWERdirectional: shifts population in one direction
disruptive: shifts population in BOTH directions
stabilizing: shifts population towards the center
What is genetic drift? Why is it not considered a type of selection? - ANSWERany
chance in allele frequencies in a population due to chance
- it is not considered a type of selection because it does not have non-random selective
pressures
ANSWERS 100% SOLVED.
What is a good definition of evolution? Does the theory of evolution include evolutionary
processes or evolutionary relationships (or both)? - ANSWERdescent with modification-
a change in allele frequencies or genetic makeup over time
What does it mean to say that evolution is a 'theory'? - ANSWERthere are lots of
different hypotheses for how evolution occurred, some have more support than others
gene - ANSWERhereditary determinant (sequence of DNA)for a trait
alleles - ANSWERdifferent versions of the same gene
genotype - ANSWERalleles found in a particular individual
phenotype - ANSWERexpressed trait of an individual
What is heritability? Why is heritability important for the process of evolution? -
ANSWERthe proportion of total phenotypic variation in a trait attributable to genetic
variation(and therefore can be passed on to offspring)
heritability equation - ANSWERℎ2 = 𝑉𝑃/𝑉𝐺
ℎ2 = 𝑉𝐺/𝑉𝐺+𝑉𝐸
VP: phenotypic variance
VG: genetic variance
VE: environmental variance
What are polygenic traits? What is pleiotropy? - ANSWERpolygenic traits are two or
more genes and interactions which vary along a continuum
pleiotropy: genes that affect more than one trait
What is plasticity? What is acclimation? Why are these processes not considered to be
evolutionary? - ANSWERplasticity: variation among individuals in form and function as a
result of environmental influences
acclimation: adjustment to change in a particular environmental factor
they are not genetic adaptations
Who are the two founders of the theory of evolution by natural selection? -
ANSWERcharles darwin and alfred russel wallace
, On what timescales do evolutionary processes occur? How do they compare to
ecological timescales? - ANSWER
What are the various lines of evidence we have that supports the theory of evolution? -
ANSWER-DNA analyses demonstrate that all of life has had a common origin
-fossil record depicts species changing throughout geological strata
-we can observe it taking place
-we can force evolution to take place
What is biological fitness? What are the two components that are often used to try to
quantify or understand biological fitness? - ANSWERthe ability of an organism to
survive AND/OR reproduce
leads to adaptive evolution
What are the three requirements for evolution by natural selection to be possible? -
ANSWER1. variation
2. heritability
3. differential fitness
What is an adaptation?
Can you understand an adaptation by considering an organism alone (without
consideration of the environment)? - ANSWERan adaptation is an inherited trait of an
organism that enhances its biological fitness
no, because adaptations consider the survival and/or reproduction in a certain
environment
What is artificial selection? What is sexual selection? How do they compare and
contrast to natural selection? - ANSWERsexual selection: form of natural selection in
which individuals with certain traits are more likely to obtain mates
artificial selection: humans modifying organisms over many generations
What are the differences between directional, disruptive, and stabilizing selection? -
ANSWERdirectional: shifts population in one direction
disruptive: shifts population in BOTH directions
stabilizing: shifts population towards the center
What is genetic drift? Why is it not considered a type of selection? - ANSWERany
chance in allele frequencies in a population due to chance
- it is not considered a type of selection because it does not have non-random selective
pressures
