BSC 108 -Final Exam Yates-Questions
with All Solved Solutions 2026.
What is micro-evolution? - Answer Changes in allele frequencies within populations, often
associated with adaptation, can be measured from one generation to the next
"small changes"
What is macro-evolution? - Answer Major changes in the history of life, origin of new species,
generates biological diversity
"big changes"
What is a species? - Answer a group of populations whose members have the potential to
interbreed with one another in nature to produce fertile offspring
What is allopatric speciation? - Answer Species evolve in geographic isolation, usually
associated with a geographic barrier that prevents members of 2 populations from mating with
each other, involves independent evolution of the populations after the barrier arises. "Physical
separation"
What is sympatric specation? - Answer Species evolve without geographic isolation,probably
associated with a genetic barrier due to a single mutational event, important in plants. "Genetic
separation"
What special circumstances are required to keep the gene pools separated in sympatric
speciation? - Answer Segregation of habitat, major alterations in mate recognition or behavior,
genetic incompatibility
The two models of the Pace of Speciation - Answer Gradualism-slow and steady accumulation
of small changes leads to production of species over vast stretches of time
Punctuated equilibrium-species diverge in spurts of rapid change, followed by long periods of
stasis
What are prezygotic barriers? Know the 5 types - Answer Prevent mating or fertilization
between species. 5 types are: temporal isolation, habitat isolation, behavioral isolation,
mechanical isolation, and gametic isolation
Example of temporal isolation - Answer Eastern and Western spotted skunks mate at different
times of year, preventing them from producing offspring even in areas where the two species
live together
, Example of habitat isolation - Answer Even though they occupy the same geographic area,
these two species of garter snakes occupy different habitats, preventing them from mating
Example of behavioral isolation - Answer Blue footed boobies and many other animals use
complex courtship displays in selecting mates. Because other species cannot mimic these
displays, offspring are not produced with members of other species
Example of mechanical isolation - Answer Snails of different species in the genus Bradybaena
may attempt to mate, but differences in the shapes of their shells prevent them from
succeeding
Example of gametic isolation - Answer Although the sperm and eggs of these two sea urchin
species are released into the water, they are unable to fuse because the proteins on the surface
of the eggs and sperm cannot bind to one another
What are postzygotic barriers? Know the 3 types - Answer Prevent survival or reproduction of
hybrid offspring. 3 types are hybrid inviability (miscarriage), hybrid sterility (sterile offspring),
and hybrid breakdown(1st generation produces sterile/weak 2nd generation)
Example of hybrid inviability - Answer Different salamander species sometimes mate, but the
offspring fail to complete development, keeping the gene pools of the two species isolated from
one another
Example of hybrid sterility - Answer Different species may mate, and produce viable offspring
that are sterile, preventing further mixing of gene pools. Mules are robust animals, offspring of
a donkey and horse, but they cannot reproduce
Example of hybrid breakdown (a post-zygotic barrier) - Answer The first generation of hybrids
may be both viable and fertile, but due to genetic factors the offspring of these hybrids are
weak, feeble, or sterile, as in domesticated rice strains.
The 8 classification levels for naming a species - Answer Domain, kingdom, phylum, class,
order, family, genus, species
The 8 classification levels for human beings - Answer Domain: Eukaryota, Kingdom: Animilia,
Phylum: Chordata, Class: Mammalia, Order: Primates, Family: Hominidae, Genus: Homo,
Species: sapiens
EACMPHHS
What is ecology? - Answer the scientific study of the interactions between organisms and their
environments
with All Solved Solutions 2026.
What is micro-evolution? - Answer Changes in allele frequencies within populations, often
associated with adaptation, can be measured from one generation to the next
"small changes"
What is macro-evolution? - Answer Major changes in the history of life, origin of new species,
generates biological diversity
"big changes"
What is a species? - Answer a group of populations whose members have the potential to
interbreed with one another in nature to produce fertile offspring
What is allopatric speciation? - Answer Species evolve in geographic isolation, usually
associated with a geographic barrier that prevents members of 2 populations from mating with
each other, involves independent evolution of the populations after the barrier arises. "Physical
separation"
What is sympatric specation? - Answer Species evolve without geographic isolation,probably
associated with a genetic barrier due to a single mutational event, important in plants. "Genetic
separation"
What special circumstances are required to keep the gene pools separated in sympatric
speciation? - Answer Segregation of habitat, major alterations in mate recognition or behavior,
genetic incompatibility
The two models of the Pace of Speciation - Answer Gradualism-slow and steady accumulation
of small changes leads to production of species over vast stretches of time
Punctuated equilibrium-species diverge in spurts of rapid change, followed by long periods of
stasis
What are prezygotic barriers? Know the 5 types - Answer Prevent mating or fertilization
between species. 5 types are: temporal isolation, habitat isolation, behavioral isolation,
mechanical isolation, and gametic isolation
Example of temporal isolation - Answer Eastern and Western spotted skunks mate at different
times of year, preventing them from producing offspring even in areas where the two species
live together
, Example of habitat isolation - Answer Even though they occupy the same geographic area,
these two species of garter snakes occupy different habitats, preventing them from mating
Example of behavioral isolation - Answer Blue footed boobies and many other animals use
complex courtship displays in selecting mates. Because other species cannot mimic these
displays, offspring are not produced with members of other species
Example of mechanical isolation - Answer Snails of different species in the genus Bradybaena
may attempt to mate, but differences in the shapes of their shells prevent them from
succeeding
Example of gametic isolation - Answer Although the sperm and eggs of these two sea urchin
species are released into the water, they are unable to fuse because the proteins on the surface
of the eggs and sperm cannot bind to one another
What are postzygotic barriers? Know the 3 types - Answer Prevent survival or reproduction of
hybrid offspring. 3 types are hybrid inviability (miscarriage), hybrid sterility (sterile offspring),
and hybrid breakdown(1st generation produces sterile/weak 2nd generation)
Example of hybrid inviability - Answer Different salamander species sometimes mate, but the
offspring fail to complete development, keeping the gene pools of the two species isolated from
one another
Example of hybrid sterility - Answer Different species may mate, and produce viable offspring
that are sterile, preventing further mixing of gene pools. Mules are robust animals, offspring of
a donkey and horse, but they cannot reproduce
Example of hybrid breakdown (a post-zygotic barrier) - Answer The first generation of hybrids
may be both viable and fertile, but due to genetic factors the offspring of these hybrids are
weak, feeble, or sterile, as in domesticated rice strains.
The 8 classification levels for naming a species - Answer Domain, kingdom, phylum, class,
order, family, genus, species
The 8 classification levels for human beings - Answer Domain: Eukaryota, Kingdom: Animilia,
Phylum: Chordata, Class: Mammalia, Order: Primates, Family: Hominidae, Genus: Homo,
Species: sapiens
EACMPHHS
What is ecology? - Answer the scientific study of the interactions between organisms and their
environments
