SBI3U Evolution unit test 2 Question
and answers already passed 2025
1. List the 4 principles of Natural Selection
i) _________________________________________________
ii) _________________________________________________
iii) ________________________________________________
iv)_________________________________________________ - correct
answer i. Variation
ii. Overproduction
iii. Adaptation
iv. Descent with modification
2. List the techniques that scientists can apply to determine the relationship
between organisms
i) _________________________________________________
ii) _________________________________________________
iii) ________________________________________________
iv)_________________________________________________ - correct
answer i. DNA sequence analysis
ii. Comparative Anatomy
iii. Protein comparisons
iv. Embryology
3. Why are vestigial structures considered critical evidence of evolution? -
correct answer Vestigial structures are considered to be critical evidence of
evolution because they are homologous to full-size features and evidence of
common ancestry among organisms that share them.
,4. Why is heredity important for both natural and artificial selection? - correct
answer Heritability is important for both natural and artificial selection
because only heritable traits can be selected for by either natural or artificial
selection and passed on to offspring.
1. Evidence of evolution comes from diverse sources such as fossils,
geography, embryology and anatomy. Describe one example of evidence for
each of these sources. - correct answer . Fossils in older layers of rock tend
to have more primitive forms than those in newer layers, but there are often
homologous structures, suggesting a shared ancestor. When comparing
populations on neighboring islands or between other distinct geographic
areas, we often see that variations have arisen that are well suited t each
place, as with the Galapagos finches. Embryology shows that crabs and
barnacles are different as adults yet nearly identical as larvae. Anatomy
reveals homologous and vestigial structures such as bones in the wing of a
bat being similar to bones in the arm of a human.
2. Each of the following refers to one aspect of evolution. Explain each in
terms of natural selection.
a. Similarities among species in a particular biome - correct answer This is an
example of convergent evolution, which demonstrates the power of the
environment to select the direction of evolution. In convergent evolution,
unrelated species often come to resemble one another because they are
subject to the same environmental pressures.
2. Each of the following refers to one aspect of evolution. Explain each in
terms of natural selection.
b. Insecticide resistance - correct answer Insecticide resistance is an
example of directional selection. Some insects are resistant to a particular
chemical insecticide. The origin of this resistance is unknown, but it probably
derives from a mutation. When the environment is sprayed with that
, insecticide, the resistant insects have the selective advantage. All the
nonresistant insects die and the remaining ones breed quickly, without any
competition for resources. The new population is entirely resistant to the
insecticide.
2. Each of the following refers to one aspect of evolution. Explain each in
terms of natural selection.
c. Speciation and isolation - correct answer Anytime a population becomes
isolated from another, the two isolated populations may begin to diverge
genetically under the pressure of different selective forces in different
environments. If enough time elapses and differing selective forces are
sufficiently great, the two populations may become so different that, even if
they were brought back together, interbreeding would not occur. The two
populations would have become two different species.
How are speciation and microevolution different? - correct answer Speciation,
by which a new species evolves from a parent species, is part of
macroevolution and the increase in
biological diversity. Microevolution is the process by which changes occur
within the gene pool of a population as a
result of either chance events or natural selection. If the makeup of the gene
pool changes enough, microevolution
may lead to speciation
. What is artificial selection, and why is it called "artificial"? - correct answer
Artificial selection is directed breeding in which individuals that exhibit a
particular trait are chosen as parents of
the next generation. Artificial selection is used to produce new breeds or
varieties of plants and animals. It is called
"artificial" because it occurs in captivity rather than in a natural setting, and
humans choose which specific animals
and answers already passed 2025
1. List the 4 principles of Natural Selection
i) _________________________________________________
ii) _________________________________________________
iii) ________________________________________________
iv)_________________________________________________ - correct
answer i. Variation
ii. Overproduction
iii. Adaptation
iv. Descent with modification
2. List the techniques that scientists can apply to determine the relationship
between organisms
i) _________________________________________________
ii) _________________________________________________
iii) ________________________________________________
iv)_________________________________________________ - correct
answer i. DNA sequence analysis
ii. Comparative Anatomy
iii. Protein comparisons
iv. Embryology
3. Why are vestigial structures considered critical evidence of evolution? -
correct answer Vestigial structures are considered to be critical evidence of
evolution because they are homologous to full-size features and evidence of
common ancestry among organisms that share them.
,4. Why is heredity important for both natural and artificial selection? - correct
answer Heritability is important for both natural and artificial selection
because only heritable traits can be selected for by either natural or artificial
selection and passed on to offspring.
1. Evidence of evolution comes from diverse sources such as fossils,
geography, embryology and anatomy. Describe one example of evidence for
each of these sources. - correct answer . Fossils in older layers of rock tend
to have more primitive forms than those in newer layers, but there are often
homologous structures, suggesting a shared ancestor. When comparing
populations on neighboring islands or between other distinct geographic
areas, we often see that variations have arisen that are well suited t each
place, as with the Galapagos finches. Embryology shows that crabs and
barnacles are different as adults yet nearly identical as larvae. Anatomy
reveals homologous and vestigial structures such as bones in the wing of a
bat being similar to bones in the arm of a human.
2. Each of the following refers to one aspect of evolution. Explain each in
terms of natural selection.
a. Similarities among species in a particular biome - correct answer This is an
example of convergent evolution, which demonstrates the power of the
environment to select the direction of evolution. In convergent evolution,
unrelated species often come to resemble one another because they are
subject to the same environmental pressures.
2. Each of the following refers to one aspect of evolution. Explain each in
terms of natural selection.
b. Insecticide resistance - correct answer Insecticide resistance is an
example of directional selection. Some insects are resistant to a particular
chemical insecticide. The origin of this resistance is unknown, but it probably
derives from a mutation. When the environment is sprayed with that
, insecticide, the resistant insects have the selective advantage. All the
nonresistant insects die and the remaining ones breed quickly, without any
competition for resources. The new population is entirely resistant to the
insecticide.
2. Each of the following refers to one aspect of evolution. Explain each in
terms of natural selection.
c. Speciation and isolation - correct answer Anytime a population becomes
isolated from another, the two isolated populations may begin to diverge
genetically under the pressure of different selective forces in different
environments. If enough time elapses and differing selective forces are
sufficiently great, the two populations may become so different that, even if
they were brought back together, interbreeding would not occur. The two
populations would have become two different species.
How are speciation and microevolution different? - correct answer Speciation,
by which a new species evolves from a parent species, is part of
macroevolution and the increase in
biological diversity. Microevolution is the process by which changes occur
within the gene pool of a population as a
result of either chance events or natural selection. If the makeup of the gene
pool changes enough, microevolution
may lead to speciation
. What is artificial selection, and why is it called "artificial"? - correct answer
Artificial selection is directed breeding in which individuals that exhibit a
particular trait are chosen as parents of
the next generation. Artificial selection is used to produce new breeds or
varieties of plants and animals. It is called
"artificial" because it occurs in captivity rather than in a natural setting, and
humans choose which specific animals
