Biology 101 Exam #1 SDSU Ekdale Complete Study Guide
2026 | Latest Update | Graded A+
1. What is the hypothetic-deductive approach primarily used for in scientific
research?
To test hypotheses through observation and experimentation.
To create theories without empirical evidence.
To analyze historical data only.
To collect data without forming hypotheses.
2. During Hurricane Marilyn, 15 green iguanas were blown out to sea from the
island of Guadalupe. They floated on mats of vegetation for several weeks
until they landed on the island of Anguilla. If these green iguanas evolve
reproductive barriers and become a new species, this would be an example
of:
sympatric speciation
allopatric speciation
postzygotic barrier
a miracle
none of the above
3. If a newly discovered organism is found to have a nucleus and membrane-
bound organelles, which domain would it likely belong to?
Archaea
Prokarya
Eukarya
, Bacteria
4. Over many generations, living things become better adapted to their
environment through the process of
Homeostasis
Symbiosis
Natural selection
Development
5. If a new organism is discovered that shares characteristics with both Fungi
and Animalia, how might this affect our understanding of evolutionary
relationships?
It could suggest a more complex evolutionary history and the
possibility of convergent evolution or hybridization.
It would have no impact on our understanding of evolutionary
relationships.
It would indicate that Fungi evolved from Animalia.
It would confirm that Fungi and Animalia are the only two major
clades.
6. You are studying a large population of snails when a new road is built,
splitting the habitat of the snail into two parts. The road is too wide for the
snails to cross it; any snail that tries dies from dehydration or gets killed by a
car. Twenty years later, you return and find the snails on the opposite sides of
the road look entirely different and will not breed with each other when you
try to mate them in captivity. Your snail population has undergone
founder's effect
a bottleneck
, allopatric speciation
macroevolution
sympatric speciation
7. What is the term used to describe when one species splits to form two?
Mechanical isolation
Isolation
Sister species
Speciation
8. What is the primary evolutionary mechanism that leads to populations
becoming better adapted to their environments?
Natural selection
Gene flow
Genetic drift
Mutation
9. What is the term for the changes in DNA that lead to new traits in organisms?
Genetic mutation
Environmental factors
Genetic drift
Gene flow
10. What is an adaptation in the context of evolutionary biology?
A behavior that is learned over time.
, A physical change that occurs due to environmental factors.
A genetic mutation that occurs randomly.
A trait that enhances an organism's ability to survive and reproduce
in its environment.
11. What term is used to describe organisms that obtain their food by ingestion?
Decomposers
Producers
Autotrophs
Heterotrophs
12. Describe how isolation can contribute to the formation of new species in
evolutionary biology.
Isolation causes species to become extinct rather than evolve.
Isolation only affects physical traits, not genetic traits.
Isolation can lead to speciation by preventing gene flow between
populations, allowing them to evolve independently.
Isolation has no effect on species formation.
13. Biologists now routinely test for homology between genes in different
species. If genes are determined to be homologous, it means that they are
related _ _.
by chance mutations
by descent from a common ancestor
because of convergent evolution
in function but not structure
2026 | Latest Update | Graded A+
1. What is the hypothetic-deductive approach primarily used for in scientific
research?
To test hypotheses through observation and experimentation.
To create theories without empirical evidence.
To analyze historical data only.
To collect data without forming hypotheses.
2. During Hurricane Marilyn, 15 green iguanas were blown out to sea from the
island of Guadalupe. They floated on mats of vegetation for several weeks
until they landed on the island of Anguilla. If these green iguanas evolve
reproductive barriers and become a new species, this would be an example
of:
sympatric speciation
allopatric speciation
postzygotic barrier
a miracle
none of the above
3. If a newly discovered organism is found to have a nucleus and membrane-
bound organelles, which domain would it likely belong to?
Archaea
Prokarya
Eukarya
, Bacteria
4. Over many generations, living things become better adapted to their
environment through the process of
Homeostasis
Symbiosis
Natural selection
Development
5. If a new organism is discovered that shares characteristics with both Fungi
and Animalia, how might this affect our understanding of evolutionary
relationships?
It could suggest a more complex evolutionary history and the
possibility of convergent evolution or hybridization.
It would have no impact on our understanding of evolutionary
relationships.
It would indicate that Fungi evolved from Animalia.
It would confirm that Fungi and Animalia are the only two major
clades.
6. You are studying a large population of snails when a new road is built,
splitting the habitat of the snail into two parts. The road is too wide for the
snails to cross it; any snail that tries dies from dehydration or gets killed by a
car. Twenty years later, you return and find the snails on the opposite sides of
the road look entirely different and will not breed with each other when you
try to mate them in captivity. Your snail population has undergone
founder's effect
a bottleneck
, allopatric speciation
macroevolution
sympatric speciation
7. What is the term used to describe when one species splits to form two?
Mechanical isolation
Isolation
Sister species
Speciation
8. What is the primary evolutionary mechanism that leads to populations
becoming better adapted to their environments?
Natural selection
Gene flow
Genetic drift
Mutation
9. What is the term for the changes in DNA that lead to new traits in organisms?
Genetic mutation
Environmental factors
Genetic drift
Gene flow
10. What is an adaptation in the context of evolutionary biology?
A behavior that is learned over time.
, A physical change that occurs due to environmental factors.
A genetic mutation that occurs randomly.
A trait that enhances an organism's ability to survive and reproduce
in its environment.
11. What term is used to describe organisms that obtain their food by ingestion?
Decomposers
Producers
Autotrophs
Heterotrophs
12. Describe how isolation can contribute to the formation of new species in
evolutionary biology.
Isolation causes species to become extinct rather than evolve.
Isolation only affects physical traits, not genetic traits.
Isolation can lead to speciation by preventing gene flow between
populations, allowing them to evolve independently.
Isolation has no effect on species formation.
13. Biologists now routinely test for homology between genes in different
species. If genes are determined to be homologous, it means that they are
related _ _.
by chance mutations
by descent from a common ancestor
because of convergent evolution
in function but not structure
