IB 150: Unit 3 How Life Evolves Questions With Complete
Solutions
_ is likely the most common mode of selection in populations
during long periods of stasis (lack of phenotypic change).
Correct Answers Stabilizing Selection
'Maximum parsimony' is a general principle with broad
application in science, which states that: Correct Answers In the
absence of additional information, the explanation that makes
the least unsupported assumptions is the most likely
(FLIEs/Prof) Why can he make this prediction? - Which
assumption of the Hardy-Weinberg principle would be
completely violated if the two populations are separate
biological species? Correct Answers individuals choose other
individuals at random to mate with
A particular recessive genetic disorder is fatal before birth, so
there are no homozygous recessive individuals. In a particular
population, one in 15 individuals is a carrier for this disorder.
What are the allele frequencies of the dominant (p) and recessive
(q) alleles in this population? Correct Answers p = 0.967, q =
0.033
A population of 500 jackrabbits has two alleles, FBand FW, for
a locus that codes for fur color. FBFBindividuals have black fur,
FBFW individuals have gray fur,FWFWindividuals have white
fur. 250 individuals are black, 150 individuals are gray and 100
individuals are white. What are the observed genotype
,frequencies in this population? Correct Answers 0.50, 0.30,
0.20
A small population of wolves was reintroduced to southern New
Mexico 20 years ago. Within the population at that time were
two different alleles (A1 and A2) for a particular gene that
affects coat color. A recent analysis shows that there is only one
allele (A2) in that population today, after only three generations.
Which of the following mechanisms are potential reasons for
this observation? Correct Answers natural selection AND/OR
genetic drift
A species of seagulls exists as a large number of different
populations on separate islands of the Azores archipelago. Both
black and white gulls are present. The black-colored seagull is
due to a dominant allele (M). Mm and MM individuals are
black, and mm individuals are white. During a storm, two males
and two females are blown 300 miles West, to an isolated island
uninhabited by seagulls. They reproduce and found a new
population. They cannot disperse back to the original habitat,
nor can any new seagulls cross to the new island. Three of the
original colonists were white-colored gulls and one was black.
Genotyping shows the single black gull to be heterozygous.
What is the frequency of the recessive (m) allele in this new
population? Correct Answers .875
A virus killed most of the seals in the North Sea (e.g., reduced
the population from 8000 to 800).What is this an example of?
Correct Answers population bottleneck
, According to the information in the scenario above, which of the
graphs above represents selection pressures on male versus
female guppies: Correct Answers . Males experience BOTH
selection pressures, females experience selection pressure
All phenotypic traits of an organism are adaptations. Correct
Answers False
At which position should you place the node to incorporate the
species represented by the following "card"? triangle line circle
Correct Answers Position E
Based on the most parsimonious solution, what must have
happened in the evolutionary history of the species represented
by the card in question 2 after the split from its most recent
common ancestor with another species shown in the cladogram?
Correct Answers Evolutionary loss of the trait represented by a
square.
Based only on the information shown in the figure above, what
is the most likely conclusion that you can reach about the
function of the three listed genes? eyes Correct Answers Both
the RX and PAX6 genes induce the initial differentiation of cells
in an eye-region near the front end of the embryo that may later
lead to the formation of a light-sensitive organ in all animals that
develop either a patch of light-sensitive cells or more complex
eyes.,
The gene for opsin is most likely involved in the differentiation
of light-sensitive cells, but not in the induction of tissues to form
simple patches of light sensitive cells or more complex eyes.,
Solutions
_ is likely the most common mode of selection in populations
during long periods of stasis (lack of phenotypic change).
Correct Answers Stabilizing Selection
'Maximum parsimony' is a general principle with broad
application in science, which states that: Correct Answers In the
absence of additional information, the explanation that makes
the least unsupported assumptions is the most likely
(FLIEs/Prof) Why can he make this prediction? - Which
assumption of the Hardy-Weinberg principle would be
completely violated if the two populations are separate
biological species? Correct Answers individuals choose other
individuals at random to mate with
A particular recessive genetic disorder is fatal before birth, so
there are no homozygous recessive individuals. In a particular
population, one in 15 individuals is a carrier for this disorder.
What are the allele frequencies of the dominant (p) and recessive
(q) alleles in this population? Correct Answers p = 0.967, q =
0.033
A population of 500 jackrabbits has two alleles, FBand FW, for
a locus that codes for fur color. FBFBindividuals have black fur,
FBFW individuals have gray fur,FWFWindividuals have white
fur. 250 individuals are black, 150 individuals are gray and 100
individuals are white. What are the observed genotype
,frequencies in this population? Correct Answers 0.50, 0.30,
0.20
A small population of wolves was reintroduced to southern New
Mexico 20 years ago. Within the population at that time were
two different alleles (A1 and A2) for a particular gene that
affects coat color. A recent analysis shows that there is only one
allele (A2) in that population today, after only three generations.
Which of the following mechanisms are potential reasons for
this observation? Correct Answers natural selection AND/OR
genetic drift
A species of seagulls exists as a large number of different
populations on separate islands of the Azores archipelago. Both
black and white gulls are present. The black-colored seagull is
due to a dominant allele (M). Mm and MM individuals are
black, and mm individuals are white. During a storm, two males
and two females are blown 300 miles West, to an isolated island
uninhabited by seagulls. They reproduce and found a new
population. They cannot disperse back to the original habitat,
nor can any new seagulls cross to the new island. Three of the
original colonists were white-colored gulls and one was black.
Genotyping shows the single black gull to be heterozygous.
What is the frequency of the recessive (m) allele in this new
population? Correct Answers .875
A virus killed most of the seals in the North Sea (e.g., reduced
the population from 8000 to 800).What is this an example of?
Correct Answers population bottleneck
, According to the information in the scenario above, which of the
graphs above represents selection pressures on male versus
female guppies: Correct Answers . Males experience BOTH
selection pressures, females experience selection pressure
All phenotypic traits of an organism are adaptations. Correct
Answers False
At which position should you place the node to incorporate the
species represented by the following "card"? triangle line circle
Correct Answers Position E
Based on the most parsimonious solution, what must have
happened in the evolutionary history of the species represented
by the card in question 2 after the split from its most recent
common ancestor with another species shown in the cladogram?
Correct Answers Evolutionary loss of the trait represented by a
square.
Based only on the information shown in the figure above, what
is the most likely conclusion that you can reach about the
function of the three listed genes? eyes Correct Answers Both
the RX and PAX6 genes induce the initial differentiation of cells
in an eye-region near the front end of the embryo that may later
lead to the formation of a light-sensitive organ in all animals that
develop either a patch of light-sensitive cells or more complex
eyes.,
The gene for opsin is most likely involved in the differentiation
of light-sensitive cells, but not in the induction of tissues to form
simple patches of light sensitive cells or more complex eyes.,
