DREXEL BIO 141 EXAM 3 QUESTIONS
AND ANSWERS
Evolution - Correct Answers -A genetic change in the population
Natural Selection - Correct Answers -the consequence of certain individual organisms in
a population being born with characteristics that enable them to survive better and
reproduce more than the offspring of other individuals in the population
Two important and unexpected patterns - Correct Answers -1. Traits exhibited by
species
2. Similarity between the fossils of extinct species and the living species in that same
area
Agents of Evolutionary Change - Correct Answers -1. Natural selection
2. Genetic drift
3. Bottleneck and founder effect
4. Gene flow
5. Sexual selection
Genetic Drift - Correct Answers -a random change in allele frequencies in a population
Fixation - Correct Answers -no more variability in the population for the gene
An ecosystem ecologist - Correct Answers -which type of person would study the
changing system?
Effect of greenhouse gases - Correct Answers -prevents heat from escaping
Species Diversity - Correct Answers -Richness is high, abundance is evenly dispersed
Founder Effect - Correct Answers -A small number of individuals may leave a
population and become the founding members of a new, isolated population
Population Bottleneck - Correct Answers -A dramatic but short-lived reduction in
population size
Migration (gene flow) - Correct Answers -the movement of some individuals of a species
from one population to another
3 conditions of natural selection - Correct Answers -1. There must be variation for the
particular trait within a population
, 2.That variation must be inheritable
3. Individuals with one version of the trait must produce more offspring than those with a
different version of the trait
Sexual Selection - Correct Answers -a form of natural selection that depends on an
individual's ability to obtain a mate
Survival of the Fittest - Correct Answers -Traits causing individuals to have more
offspring than others become more prevalent
False - Correct Answers -T/F
Natural selection leads to perfect organisms
True - Correct Answers -T/F
Natural selection can change the traits seen in a population in several ways
Species - Correct Answers -a population that is capable of interbreeding to produce
healthy, fertile offspring
Prezygotic barriers - Correct Answers -prevent mating between species
True - Correct Answers -T/F
Behavior is part of an organism's phenotype
Prepared Learning - Correct Answers -Behaviors that are learned easily and by all (or
nearly all) individuals
Altruistic behaviors - Correct Answers -behaviors that come at a cost to the individual
doing the behavior while benefiting the recipient
Hamilton's Rule - Correct Answers -acting in their own genes' best interests
Reproductive Investment - Correct Answers -There are big differences in how much
males and females invest in reproduction
Female - Correct Answers -produces the larger gamete
Male - Correct Answers -produces the smaller gamete
Paternity uncertainty - Correct Answers -males and females are vulnerable at different
stages of the reproductive exchange
False - Correct Answers -T/F
The sex that invests the least will be more discriminating
Factors in Mate Selection - Correct Answers -1. Courtship Rituals
AND ANSWERS
Evolution - Correct Answers -A genetic change in the population
Natural Selection - Correct Answers -the consequence of certain individual organisms in
a population being born with characteristics that enable them to survive better and
reproduce more than the offspring of other individuals in the population
Two important and unexpected patterns - Correct Answers -1. Traits exhibited by
species
2. Similarity between the fossils of extinct species and the living species in that same
area
Agents of Evolutionary Change - Correct Answers -1. Natural selection
2. Genetic drift
3. Bottleneck and founder effect
4. Gene flow
5. Sexual selection
Genetic Drift - Correct Answers -a random change in allele frequencies in a population
Fixation - Correct Answers -no more variability in the population for the gene
An ecosystem ecologist - Correct Answers -which type of person would study the
changing system?
Effect of greenhouse gases - Correct Answers -prevents heat from escaping
Species Diversity - Correct Answers -Richness is high, abundance is evenly dispersed
Founder Effect - Correct Answers -A small number of individuals may leave a
population and become the founding members of a new, isolated population
Population Bottleneck - Correct Answers -A dramatic but short-lived reduction in
population size
Migration (gene flow) - Correct Answers -the movement of some individuals of a species
from one population to another
3 conditions of natural selection - Correct Answers -1. There must be variation for the
particular trait within a population
, 2.That variation must be inheritable
3. Individuals with one version of the trait must produce more offspring than those with a
different version of the trait
Sexual Selection - Correct Answers -a form of natural selection that depends on an
individual's ability to obtain a mate
Survival of the Fittest - Correct Answers -Traits causing individuals to have more
offspring than others become more prevalent
False - Correct Answers -T/F
Natural selection leads to perfect organisms
True - Correct Answers -T/F
Natural selection can change the traits seen in a population in several ways
Species - Correct Answers -a population that is capable of interbreeding to produce
healthy, fertile offspring
Prezygotic barriers - Correct Answers -prevent mating between species
True - Correct Answers -T/F
Behavior is part of an organism's phenotype
Prepared Learning - Correct Answers -Behaviors that are learned easily and by all (or
nearly all) individuals
Altruistic behaviors - Correct Answers -behaviors that come at a cost to the individual
doing the behavior while benefiting the recipient
Hamilton's Rule - Correct Answers -acting in their own genes' best interests
Reproductive Investment - Correct Answers -There are big differences in how much
males and females invest in reproduction
Female - Correct Answers -produces the larger gamete
Male - Correct Answers -produces the smaller gamete
Paternity uncertainty - Correct Answers -males and females are vulnerable at different
stages of the reproductive exchange
False - Correct Answers -T/F
The sex that invests the least will be more discriminating
Factors in Mate Selection - Correct Answers -1. Courtship Rituals
