BIO 200 – Final Exam Review
Questions and Answers
Artificial Selection - ANS-Genetic changes within a population which occur because
humans purposely select for specific characteristics either by choosing which organisms
to breed or by eliminating the undesirable individuals.
Natural Selection - ANS-Genetic changes within a natural population. Occurs because
of differences in the reproductive success of some individuals over others.
Pleitrophy - ANS-When one gene influences two or more seemingly unrelated
phenotypic states.
Mutation - ANS-A change in a gene or chromosome. Done by alteration of single base
units in DNA, or the deletion, insertion, or rearrangement of larger sections of genes or
chromosomes.
Genetic recombination - ANS-Process of forming new allelic combination in offspring by
EXCHANGES between genetic materials.
What produces selection? - ANS-Internal environment (genetic,
physiological/developmental) and external environment (physical and biological;
competition, predation, parasitism, food supply, sexual selection).
Selection against a dominant trait - ANS-Rapid elimination of the trait should occur.
Selection against a recessive trait - ANS-Selection will be slow to remove the "a" allele
in complete dominance because it's hidden in the heterozygous condition "Aa."
Selection favoring heterozygotes can only happen if incomplete or co-dominance
because the trait is expressed (sickle-cell anemia).
List all the different relationships between species - ANS-Neutralism (0/0), Mutualism
(+/+), Competition (-/-), Predation (-/+), Parasitism (-/+), Commensalism (0/+),
Amensalism (-/0)
Resource-resource relationship (mutualistic) - ANS-Resources are exchanged (typically
nutrients)
Service-resource relationship (mutualistic) - ANS-Services are exchanged for resources
(usually nutrients). Example: squirrels get nuts and nuts are dispersed.
,Service-service relationship (mutualistic) - ANS-Services are exchanged. Example: sea
anemones and clown fish.
Interspecific resource competition - ANS-BETWEEN species. 1) scramble competition:
same resource at different times. 2) contest competition: same resource at same time.
Intraspecific resource competition - ANS-WITHIN a species.
Competitive exclusion principle - ANS-Complete competitors cannot co-exist if
resources are limited.
Resource partitioning - ANS-When two species divide a resource based on behavioral
or morphological (form and structure of organisms/specific structural features) variation.
Goal is to limit competition as much as possible.
Types of resource partitioning - ANS-Habitat partitioning, temporal partitioning, seasonal
partitioning, food type/foraging strategy partitioning.
Keystone species - ANS-Species that plays a critical role in maintaining the structure of
an ecological community and whose impact on it is greater than would typically be
expected. Examples: elephants destroy trees, making room for grass species.
Sexual selection - ANS-Competition among individuals of the same sex for reproductive
success
Male competition - ANS-- Males fighting
- Threat displays
- Sperm competition
- Sperm removal
- Male guarding
Sexual dimorphism - ANS-Difference in morphology between male and females of the
same species. Includes differences in size, coloration, or body structure between the
sexes.
Female choice - ANS-- Some mate preferences are learned
- Some mate preferences are genetic
- Runaway selection (evolution of exaggerated male ornamentation by persistent &
directional female choice)
Beauty Hypothesis - ANS-Female is choosing mate simply because of its beauty.
Selective Advantage Hypothesis - ANS-Traits selected with potential for reproductive
success. Trait shows health.
,Handicap Hypothesis - ANS-Female is choosing those which have suffered even in
spite of possible disadvantages. Shows that they are extraordinarily fit and strong
enough to be able to overcome this disadvantage.
Individuals cooperate due to... - ANS-Food capture, predator avoidance, protection,
build shelters, care giving, reproduction, altruism, kin selection.
Kin selection - ANS-Form of natural selection that favors traits that increase survival or
reproduction of an individual's kin at the expense of an individual. Involves altruism ---
an act by an individual that increases fitness of others that that individual's expense.
This can also increase the chances that your genes will survive.
Epigenetics - ANS-Epigenesis occurs when the DNA of a cell is regulated to be turned
on or off... change of gene expression through the modification of DNA without actually
changing the DNA sequence.
(example: identical twins = same DNA, become more different as they get more
epigenetic tags)
How do parasites affect hosts? - ANS-(1) Consume energy, (2) destroy cells, (3)
obstruct functions of organs, (4) produce toxins
Results of parasitism - ANS-1. Can kill the host
2. Can make them sick and therefore easier for predators to catch and easier for
parasites to infect
3. Can change behavior of host.
Results of Parasite-Host interactions - ANS-1. Host can become extinct across entire
range
2. Identity switching to avoid immune system (African sleeping sickness: parasite
switches surface proteins so the immune system cannot identify it)
Effects of predation - ANS-1. Prey becomes extinct and predator becomes extinct
2. Predator becomes extinct and prey population explodes
Co-existence - ANS-Unstable equilibrium, short term irregular balance, temporary local
extinction and re-immigration.
How do the prey avoid predation? - ANS-Camouflage by mimicry of objects, camouflage
by hiding, camouflage by countershading, camouflage by disruptive patterning, batesian
mimicry, mullerian mimicry
Batesian Mimicry - ANS-Mimicking dangerous or unpalatable species. They are not
actually harmful.
, Mullerian Mimicry - ANS-All species are unpalatable. Actually harmful. Form of
mutualism.
Co-existence - Prey Switching - ANS-Generalized predators, specialized predators
(pandas only eat bamboo), different secondary food sources
Evolutionary "Arm's Race" - ANS-Occurs between predators and prey. Only the best
prey and predators survive (idea of survival of the fittest).
Typological (morphological) species - ANS-Groups of organisms that share some
characteristics which are different than other groups -- usually includes differences in
anatomy. This helps them distinguish themselves from other species.
Biological species concept - ANS-Reproductively isolated group of ACTUALLY
interbreeding natural populations that produce fertile offspring.
Sympatric speciation - ANS-Speciation that happens without the physical separation of
members of the population. Sympatric speciation is easy! Can speciate by polyploidy
(autopolyploid and allopolyploid).
Allopatric speciation - ANS-Speciation that occurs when a population is separated by a
physical barrier. Occurs due to dispersal, barriers, and continental drift. Allopatric
speciation is hard!
Problems/issues in identifying species - ANS-Polymorphic species, sibling species, ring
species, asexual species, fossil species.
Polymorphic species - ANS-Many different types of individuals. Poly = many, morphic =
forms
Sibling species - ANS-Virtually identical species (siblings look alike)
Ring species - ANS-Continuous gradual shift in phenotype over a large range. the end
populations cannot interbreed.
Asexual species and fossil species - ANS-Cannot use biological species definition
Reproductive Isolation Mechanisms - ANS-There are pre-zygotic and post-zygotic
barriers. This is meant to keep/prevent species from interbreeding.
Pre-zygotic barriers (in detail) - ANS-Ecological/habitat isolation: Share territory, but
occupy different regions
Behavioral isolation: (ie: frogs only respond to the calls of their own same species)
Mechanical isolation: Distinct reproductive parts.
Questions and Answers
Artificial Selection - ANS-Genetic changes within a population which occur because
humans purposely select for specific characteristics either by choosing which organisms
to breed or by eliminating the undesirable individuals.
Natural Selection - ANS-Genetic changes within a natural population. Occurs because
of differences in the reproductive success of some individuals over others.
Pleitrophy - ANS-When one gene influences two or more seemingly unrelated
phenotypic states.
Mutation - ANS-A change in a gene or chromosome. Done by alteration of single base
units in DNA, or the deletion, insertion, or rearrangement of larger sections of genes or
chromosomes.
Genetic recombination - ANS-Process of forming new allelic combination in offspring by
EXCHANGES between genetic materials.
What produces selection? - ANS-Internal environment (genetic,
physiological/developmental) and external environment (physical and biological;
competition, predation, parasitism, food supply, sexual selection).
Selection against a dominant trait - ANS-Rapid elimination of the trait should occur.
Selection against a recessive trait - ANS-Selection will be slow to remove the "a" allele
in complete dominance because it's hidden in the heterozygous condition "Aa."
Selection favoring heterozygotes can only happen if incomplete or co-dominance
because the trait is expressed (sickle-cell anemia).
List all the different relationships between species - ANS-Neutralism (0/0), Mutualism
(+/+), Competition (-/-), Predation (-/+), Parasitism (-/+), Commensalism (0/+),
Amensalism (-/0)
Resource-resource relationship (mutualistic) - ANS-Resources are exchanged (typically
nutrients)
Service-resource relationship (mutualistic) - ANS-Services are exchanged for resources
(usually nutrients). Example: squirrels get nuts and nuts are dispersed.
,Service-service relationship (mutualistic) - ANS-Services are exchanged. Example: sea
anemones and clown fish.
Interspecific resource competition - ANS-BETWEEN species. 1) scramble competition:
same resource at different times. 2) contest competition: same resource at same time.
Intraspecific resource competition - ANS-WITHIN a species.
Competitive exclusion principle - ANS-Complete competitors cannot co-exist if
resources are limited.
Resource partitioning - ANS-When two species divide a resource based on behavioral
or morphological (form and structure of organisms/specific structural features) variation.
Goal is to limit competition as much as possible.
Types of resource partitioning - ANS-Habitat partitioning, temporal partitioning, seasonal
partitioning, food type/foraging strategy partitioning.
Keystone species - ANS-Species that plays a critical role in maintaining the structure of
an ecological community and whose impact on it is greater than would typically be
expected. Examples: elephants destroy trees, making room for grass species.
Sexual selection - ANS-Competition among individuals of the same sex for reproductive
success
Male competition - ANS-- Males fighting
- Threat displays
- Sperm competition
- Sperm removal
- Male guarding
Sexual dimorphism - ANS-Difference in morphology between male and females of the
same species. Includes differences in size, coloration, or body structure between the
sexes.
Female choice - ANS-- Some mate preferences are learned
- Some mate preferences are genetic
- Runaway selection (evolution of exaggerated male ornamentation by persistent &
directional female choice)
Beauty Hypothesis - ANS-Female is choosing mate simply because of its beauty.
Selective Advantage Hypothesis - ANS-Traits selected with potential for reproductive
success. Trait shows health.
,Handicap Hypothesis - ANS-Female is choosing those which have suffered even in
spite of possible disadvantages. Shows that they are extraordinarily fit and strong
enough to be able to overcome this disadvantage.
Individuals cooperate due to... - ANS-Food capture, predator avoidance, protection,
build shelters, care giving, reproduction, altruism, kin selection.
Kin selection - ANS-Form of natural selection that favors traits that increase survival or
reproduction of an individual's kin at the expense of an individual. Involves altruism ---
an act by an individual that increases fitness of others that that individual's expense.
This can also increase the chances that your genes will survive.
Epigenetics - ANS-Epigenesis occurs when the DNA of a cell is regulated to be turned
on or off... change of gene expression through the modification of DNA without actually
changing the DNA sequence.
(example: identical twins = same DNA, become more different as they get more
epigenetic tags)
How do parasites affect hosts? - ANS-(1) Consume energy, (2) destroy cells, (3)
obstruct functions of organs, (4) produce toxins
Results of parasitism - ANS-1. Can kill the host
2. Can make them sick and therefore easier for predators to catch and easier for
parasites to infect
3. Can change behavior of host.
Results of Parasite-Host interactions - ANS-1. Host can become extinct across entire
range
2. Identity switching to avoid immune system (African sleeping sickness: parasite
switches surface proteins so the immune system cannot identify it)
Effects of predation - ANS-1. Prey becomes extinct and predator becomes extinct
2. Predator becomes extinct and prey population explodes
Co-existence - ANS-Unstable equilibrium, short term irregular balance, temporary local
extinction and re-immigration.
How do the prey avoid predation? - ANS-Camouflage by mimicry of objects, camouflage
by hiding, camouflage by countershading, camouflage by disruptive patterning, batesian
mimicry, mullerian mimicry
Batesian Mimicry - ANS-Mimicking dangerous or unpalatable species. They are not
actually harmful.
, Mullerian Mimicry - ANS-All species are unpalatable. Actually harmful. Form of
mutualism.
Co-existence - Prey Switching - ANS-Generalized predators, specialized predators
(pandas only eat bamboo), different secondary food sources
Evolutionary "Arm's Race" - ANS-Occurs between predators and prey. Only the best
prey and predators survive (idea of survival of the fittest).
Typological (morphological) species - ANS-Groups of organisms that share some
characteristics which are different than other groups -- usually includes differences in
anatomy. This helps them distinguish themselves from other species.
Biological species concept - ANS-Reproductively isolated group of ACTUALLY
interbreeding natural populations that produce fertile offspring.
Sympatric speciation - ANS-Speciation that happens without the physical separation of
members of the population. Sympatric speciation is easy! Can speciate by polyploidy
(autopolyploid and allopolyploid).
Allopatric speciation - ANS-Speciation that occurs when a population is separated by a
physical barrier. Occurs due to dispersal, barriers, and continental drift. Allopatric
speciation is hard!
Problems/issues in identifying species - ANS-Polymorphic species, sibling species, ring
species, asexual species, fossil species.
Polymorphic species - ANS-Many different types of individuals. Poly = many, morphic =
forms
Sibling species - ANS-Virtually identical species (siblings look alike)
Ring species - ANS-Continuous gradual shift in phenotype over a large range. the end
populations cannot interbreed.
Asexual species and fossil species - ANS-Cannot use biological species definition
Reproductive Isolation Mechanisms - ANS-There are pre-zygotic and post-zygotic
barriers. This is meant to keep/prevent species from interbreeding.
Pre-zygotic barriers (in detail) - ANS-Ecological/habitat isolation: Share territory, but
occupy different regions
Behavioral isolation: (ie: frogs only respond to the calls of their own same species)
Mechanical isolation: Distinct reproductive parts.
