Pregunta 1
Pregunta
Why don’t ecosystems eventually run out of energy?
Respuesta
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because there are secondary producers
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because photosynthesis is exergonic
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because they are open systems
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because they are closed systems
Pregunta 2
Pregunta
Which of the following is most likely to be associated with dynamic equilibrium in an ecosystem?
Respuesta
-
a positive feedback loop
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a negative feedback loop
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homeorhesis
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pulsing states
Pregunta 3
Pregunta
A coyote eats a rabbit, and burns off much of the calories it gains in maintaining body temperature. In this instance, what can we say about entropy and energy?
Respuesta
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entropy has decreased, available useful energy has increased
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entropy has decreased, available useful energy has decreased
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entropy has increased, available useful energy has increased
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entropy has increased, available useful energy has decreased
Pregunta 4
Pregunta
Light is often more limiting in aquatic ecosystems than in terrestrial ecosystems.
Pregunta 5
Pregunta
The effects of temperature and precipitation on Net Primary Productivity (NPP) are independent.
Pregunta 6
Pregunta
Ecosystem X houses species with extremely large niches. What can we say is likely regarding the resistance and resilience of this ecosystem?
Respuesta
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high resistance and high resilience
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low resistance, intermediate resilience
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high resilience, intermediate resistance
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low resistance and low resilience
Pregunta 7
Pregunta
You estimate kilograms of corn plants (including stalks, shoots, leaves, etc) produced per square meter per year in a field outside of Waterloo. This is best characterized as an estimate of:
Pregunta 8
Pregunta
Ecosystem “A” retains most of its food web structure and species composition through a period marked by heavy pollution. Nearby Ecosystem ‘B’ however loses 50% of its species diversity and feeding links. Ecosystem ‘A’ is:
Respuesta
-
more resistant that Ecosystem 'B'
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more resilient than Ecosystem 'B'
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in a positive feedback loop
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both A and B
Pregunta 9
Pregunta
Warm nutrient rich conditions favour growth of an algal bloom in a lake. In fall, the decomposing algae releases yet more nutrients into the lake which leads to an even worse algal bloom the following spring. This is an example of:
Respuesta
-
negative feedback
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a trophic cascade
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homeostasis
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positive feedback
Pregunta 10
Pregunta
Energy is recycled in detrital food chains.
Pregunta 11
Pregunta
Which of the following ecosystems would you likely observe the highest trophic efficiency in?
Pregunta 12
Pregunta
Which of the following is likely to have the highest concentrations of a biomagnifying contaminant?
Respuesta
-
primary producer
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primary consumer
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secondary consumer
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tertiary consumer
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all are equal
Pregunta 13
Pregunta
High level carnivores are often part of only one type of food chain – either grazing or detrital.
Pregunta 14
Pregunta
Neither energy nor biomass pyramids can be inverted/upside down (ie. larger at the top than the bottom).
Pregunta 15
Pregunta
Grazing and detrital food chains are independent are not connected.
Pregunta 16
Pregunta
You are studying a three-level food chain (primary producers, herbivores, carnivores). 5000 calories of plant energy are produced. How many of these calories will be convertes into carnivore tissue?
Respuesta
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5 calories
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50 calories
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500 calories
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5000 calories
Pregunta 17
Pregunta
A snail that feeds on dead leaves is best characterized as:
Respuesta
-
a saprophage; part of the detrital food chain
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a biophage; part of the grazing food chain
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a biophage; part of the detrital food chain
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a saprophage; part of the grazing food chain
Pregunta 18
Pregunta
What variable(s) affect(s) the rate of decomposition? Select all that apply, if more than one.
Respuesta
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amount of lignin
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temperature
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moisture
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oxygen availability
Pregunta 19
Pregunta
What are the eventual end products of decomposition?
Respuesta
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inorganic nutrients
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secondary productivity
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organic matter
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detritus
Pregunta 20
Pregunta
Where would we expect nutrient concentrations in streams to be highest?
Respuesta
-
bottom of a vegetated valley
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bottom of a recently logged valley
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all of the above are equal
Pregunta 21
Pregunta
What human activities have been implicated in dropped water tables?
Pregunta 22
Pregunta
Fertilizing a grassland with nitrogen is MOST likely to result in:
Respuesta
-
increase in productivity, increase in species richness
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increase in productivity, no change in species richness
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increase in productivity, transition to N-fixing species
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increase in productivity, decrease in species richness
Pregunta 23
Pregunta
Increasing temperatures are causing permafrost and tundra to melt. This causes faster decomposition rates and carbon release, and is an example of:
Respuesta
-
positive feedback
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negative feedback
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neutral feedback
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none of the above
Pregunta 24
Pregunta
Which of the following is/are potential direct or indirect cause(s) of climate warming? (Select all that apply)
Pregunta 25
Pregunta
Which of the countries below uses the most oil per capita?
Respuesta
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China
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Canada
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India
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Australia
Pregunta 26
Pregunta
Climate warming is thought to be related to which of the following ecological observations? (Select all that apply, if more than one)
Respuesta
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changes in species' ranges
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changes in allele frequencies within species
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changes in timing of seasonal life history events, such as flowering
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changes in extinction rates
Pregunta 27
Pregunta
Globally, we know that climate-induced increases in terrestrial NPP will compensate up for climate-induced decreases in marine NPP.
Pregunta 28
Pregunta
Nutrient run-off into marine coastal environments can cause:
Respuesta
-
formation of toxic algal blooms
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formation of anoxic zones
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short-term increases in primary productivity
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all of the above
Pregunta 29
Pregunta
What factor(s) is/are affecting the health of coral reef ecosystems?
Respuesta
-
increasing temperatures
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ocean acidification
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pollution
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all of the above
Pregunta 30
Pregunta
Which is NOT a leading factor in explaining why climate change is increasing terrestrial NPP?
Pregunta 31
Pregunta
Why is marine NPP thought to be decreasing (leading explanation)?