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Biology 182 Module 3 Questions and Answers with
Solutions UPDATED!!!
Stabilizing Selection - ANSWER form of natural selection by
which the center of the curve remains in its current position;
occurs when individuals near the center of a distribution curve
have higher fitness than individuals at either end.
The mean and standard deviation of a trait remains similar over
time.
directional selection - ANSWER Form of natural selection, The
mean phenotype shifts in a particular direction. For this process
to work, the environment must change slowly enough for the
population to persist. If the environment changes too quickly,
no members of the population will be able to reproduce,
leading to extinction.
disruptive selection - ANSWER form of natural selection in
which a single curve splits into two; occurs when individuals at
the upper and lower ends of a distribution curve have higher
fitness than individuals near the middle
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natural selection - ANSWER variation in phenotypes, heribility,
reporduction
variation in phenotype - ANSWER Different species have
different genes, but same species have same genes but
different versions of them (alleles).
Genes and alleles make up genotype - difference in genotype =
variation in phenotype.
phenotypic selection - ANSWER The component of the natural
selection process in which some traits result in greater fitness
(reproduce)than others
directional selection formula - ANSWER y=bx+c
y=relative fitness
x= trait value
b= strength of selection
c= parameter
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True or False? If the slope of the relationship between the
phenotype and fitness is positive, natural selection would
decrease the phenotype over generations. - ANSWER false
because a positive relationship would lead to an increase in the
phenotype over generations, not a decrease.
stabilizing selection example - ANSWER y=ax^2+bx+c
y= relative fitness
x= trait value
a/b= strength of selection
c= parameter
y=ax^+bx+c - ANSWER ax^2 will either be +/- or bx will be either
+/- only one can be postive and only one can be negative. Need
to find which one is the negative and positive.
This will show if graphs keeps going up or down.
True or False? If the parameter for the squared term is negative,
natural selection will likely stabilize the phenotype at an
intermediate value. - ANSWER True. That if the squared term is
negative, then selection will likely stabilize. Because it depends
on how large the parameter is for the squared term, the A.
Biology 182 Module 3 Questions and Answers with
Solutions UPDATED!!!
Stabilizing Selection - ANSWER form of natural selection by
which the center of the curve remains in its current position;
occurs when individuals near the center of a distribution curve
have higher fitness than individuals at either end.
The mean and standard deviation of a trait remains similar over
time.
directional selection - ANSWER Form of natural selection, The
mean phenotype shifts in a particular direction. For this process
to work, the environment must change slowly enough for the
population to persist. If the environment changes too quickly,
no members of the population will be able to reproduce,
leading to extinction.
disruptive selection - ANSWER form of natural selection in
which a single curve splits into two; occurs when individuals at
the upper and lower ends of a distribution curve have higher
fitness than individuals near the middle
,2|Page
natural selection - ANSWER variation in phenotypes, heribility,
reporduction
variation in phenotype - ANSWER Different species have
different genes, but same species have same genes but
different versions of them (alleles).
Genes and alleles make up genotype - difference in genotype =
variation in phenotype.
phenotypic selection - ANSWER The component of the natural
selection process in which some traits result in greater fitness
(reproduce)than others
directional selection formula - ANSWER y=bx+c
y=relative fitness
x= trait value
b= strength of selection
c= parameter
, 3|Page
True or False? If the slope of the relationship between the
phenotype and fitness is positive, natural selection would
decrease the phenotype over generations. - ANSWER false
because a positive relationship would lead to an increase in the
phenotype over generations, not a decrease.
stabilizing selection example - ANSWER y=ax^2+bx+c
y= relative fitness
x= trait value
a/b= strength of selection
c= parameter
y=ax^+bx+c - ANSWER ax^2 will either be +/- or bx will be either
+/- only one can be postive and only one can be negative. Need
to find which one is the negative and positive.
This will show if graphs keeps going up or down.
True or False? If the parameter for the squared term is negative,
natural selection will likely stabilize the phenotype at an
intermediate value. - ANSWER True. That if the squared term is
negative, then selection will likely stabilize. Because it depends
on how large the parameter is for the squared term, the A.
