BIO 100 EXAM 1 2025 QUESTIONS
AND ANSWERS
which of the following is the most complete example of an ecosystem
a. all of the brook trout in a 500 square hectare river drainage system
b. all of the plant animals and decomposers that live on a dairy farm
c. a pond and all of the plant and animal species that live in it
d. the complicated interactions of the different plant and animal species in the
woods near umaine campus
e. all of the organisms and their physical environment in and around the stillwater
river - ....ANSWER ...-e. all of the organisms and their physical environment
in and around stillwater river
Owls eat rats, mice, shrews, and small birds. Assume that, over a period of time, an
owl consumes 5,000 J of animal material. The owl loses 2,300 J in feces and owl
pellets and uses 2,600 J for cellular respiration. What is the production efficiency of
this owl?
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,a. 0.02%
b. 1%
c. 4%
d. 10%
e. 40% - ....ANSWER ...-c. 4%
when considering biogeochemical cycles a major reservoir for both bioavailable
carbon and nitrogen is....
a. the open ocean
b. the atmosphere
c. the earths core
d. rocks
e. clouds - ....ANSWER ...-b. the atmosphere
For most terrestrial ecosystems, pyramids composed of species abundances,
biomass, and energy are similar in that they have a broad base and a narrow top.
The primary reason for this pattern is that _____.
a. secondary consumers and top carnivores require less energy than producers
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, b. at each step energy is lost from the system because of the second law of
thermodynamics
c. as matter passes through ecosystems some of it is lost to the environment
d. biomagnification of toxic materials limits the secondary consumers and top
carnivores
e. top carnivores and secondary consumers have a more general diet than primary
producers - ....ANSWER ...-b. at each step energy is lost from the system
because of the second law of thermodynamics
which trophic level is the most vulnerable to going extinct?
a. producer level
b. primary consumer level
c. secondary consumer level
d. tertiary consumer level
e. decomposer level - ....ANSWER ...-d. tertiary consumer level
through time the lineage that led to modern whales shows a change from four
limbed land animals to aquatic animals with two limbs that function as flippers this
change is best described by...
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AND ANSWERS
which of the following is the most complete example of an ecosystem
a. all of the brook trout in a 500 square hectare river drainage system
b. all of the plant animals and decomposers that live on a dairy farm
c. a pond and all of the plant and animal species that live in it
d. the complicated interactions of the different plant and animal species in the
woods near umaine campus
e. all of the organisms and their physical environment in and around the stillwater
river - ....ANSWER ...-e. all of the organisms and their physical environment
in and around stillwater river
Owls eat rats, mice, shrews, and small birds. Assume that, over a period of time, an
owl consumes 5,000 J of animal material. The owl loses 2,300 J in feces and owl
pellets and uses 2,600 J for cellular respiration. What is the production efficiency of
this owl?
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 1
,a. 0.02%
b. 1%
c. 4%
d. 10%
e. 40% - ....ANSWER ...-c. 4%
when considering biogeochemical cycles a major reservoir for both bioavailable
carbon and nitrogen is....
a. the open ocean
b. the atmosphere
c. the earths core
d. rocks
e. clouds - ....ANSWER ...-b. the atmosphere
For most terrestrial ecosystems, pyramids composed of species abundances,
biomass, and energy are similar in that they have a broad base and a narrow top.
The primary reason for this pattern is that _____.
a. secondary consumers and top carnivores require less energy than producers
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 2
, b. at each step energy is lost from the system because of the second law of
thermodynamics
c. as matter passes through ecosystems some of it is lost to the environment
d. biomagnification of toxic materials limits the secondary consumers and top
carnivores
e. top carnivores and secondary consumers have a more general diet than primary
producers - ....ANSWER ...-b. at each step energy is lost from the system
because of the second law of thermodynamics
which trophic level is the most vulnerable to going extinct?
a. producer level
b. primary consumer level
c. secondary consumer level
d. tertiary consumer level
e. decomposer level - ....ANSWER ...-d. tertiary consumer level
through time the lineage that led to modern whales shows a change from four
limbed land animals to aquatic animals with two limbs that function as flippers this
change is best described by...
....COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 3