BIO1001 Practice Question 3

Practise
Problems.



Read
the
questions
carefully,
determine
what
the
question
is
asking,
and
choose
the
best
answer.

It
is
best
to
try
these
questions
under
test-­‐like
conditions.
Put
away
all
your
notes
and
sit
in
a
quiet

area.
Give
yourself
60
minutes
to
do
these
41
questions
(includes
3
short
answer
and
2
cladogram

construction
questions).




1. Why
isn’t
inbreeding
considered
an
evolutionary
mechanism?

a. It
does
not
change
genotype
frequencies.

b. It
does
not
change
allele
frequencies.

c. It
does
not
occur
often
enough
to
be
important
in
evolution.

d. It
does
not
violate
the
assumptions
of
the
Hardy-­‐Weinberg
principle.



2. When
does
vicariance
occur?

a. Small
populations
coalesce
into
one
large
population.

b. A
population
is
fragmented
into
isolated
subpopulations.

c. Individuals
colonize
a
novel
habitat.

d. Individuals
disperse
and
found
a
new
population.



3. The
common
edible
frog
of
Europe
is
a
hybrid
between
two
species
Rana
lessonae
and
Rana

ribunda.
Both
male
and
female
hybrids
exist,
but
when
they
mate
among
themselves,
are

rarely
successful
in
producing
offspring.
What
can
you
infer
from
this
information?

a. Postzygotic
isolation
exists
between
the
two
frog
species.

b. Prezygotic
isolation
exists
between
the
two
frog
species.

c. These
two
species
are
likely
in
the
process
of
fusing
back
into
one
species.


d. These
hybrids
represent
a
separate
species
under
the
biological
species
concept.



4. Dog
breeders
maintain
the
purity
of
breeds
by
keeping
dogs
of
different
breeds
apart
when

they
are
fertile.
This
kind
of
isolation
is
most
similar
to
which
of
the
following
reproductive

isolating
mechanisms?

a. Reduced
hybrid
fertility

b. Mechanical
isolation

c. Habitat
isolation

d. Gametic
isolation



5. Two
species
of
salamanders
belonging
to
the
same
genus
occasionally
mate,
but
the
offspring

fail
to
develop
&
hatch.
What
is
the
mechanism
for
keeping
the
2
salamander
species

separate?

a.
Postzygotic
barrier;
hybrid
inviability

b.
Postzygotic
barrier;
hybrid
breakdown

c.
Prezygotic
breakdown;
hybrid
sterility

d.
Prezygotic
breakdown;
hybrid
incompatability












,

6. Islands
are
well
known
for
having
many
endemic
species
–
that
is,
species
that
are
unique
to

that
location.
What
is
a
likely
explanation
for
this
pattern?

a.
Colonizers
encounter
fewer
competitors
on
an
island,
so
they
can
diversity.

b.
Islands
are
more
complex
habitats
than
continental
mainland,
so
they
have
more
niches
for

specialization.

c.
Humans
bring
partly
or
fully
domesticated
species
with
them
when
they
arrive
on
islands.

d.
The
type
of
organism
that’s
a
good
colonizer
has
more
than
the
average
amount
of
genetic

variability,
so
it’s
more
likely
to
undergo
speciation.




7. If
two
species
of
lizards
do
not
mate
because
their
mating
rituals
differ
greatly,
this
is
known

as

a.
ecological
isolation.

b.
behavioural
isolation.

c.
temporal
isolation.

d.
mechanical
isolation.



8. An
example
of
mechanical
isolation
would
be

a.
two
organisms
that
are
pollinated
by
different
insects

b.
two
organisms
that
have
different
habitats

c.
two
organisms
that
have
incompatible
gametes

d.
two
organisms
that
have
different
mating
rituals



9. The
biological
species
concept
is
inadequate
for
grouping

a. Plants

b. Parasites

c. Asexual
organisms

d. Migratory
animals



10. In
order
for
speciation
to
occur,
what
is
true?

a. The
number
of
chromosomes
in
the
genome
must
change.

b. At
least
one
gene,
affecting
at
least
one
phenotypic
trait,
must
change.

c. Large
numbers
of
genes
that
affect
numerous
phenotypic
traits
must
change.

d. There
does
not
need
to
be
any
genetic
change.




11. Which
of
the
following
describes
the
most
likely
order
of
events
in
speciation?



a. genetic
drift,
genetic
isolation,
divergence

b. genetic
isolation,
divergence,
genetic
drift

c. divergence,
genetic
isolation,
genetic
drift

d. genetic
isolation,
genetic
drift,
divergence





12. A
mule
is
an
example
of

a. hybrid
inviability.

b. mechanical
isolation.

c. temporal
isolation.