This diagram shows a single pathway of energy moving from one organism to another.
food chain
This type of pyramid shows the relative amount of energy at each trophic level.
energy pyramid
This term describes the maximum number of organisms an ecosystem can support long-term.
carrying capacity
This process removes carbon dioxide from the atmosphere.
photosynthesis
This Earth sphere includes dissolved carbon dioxide in oceans and lakes.
hydrosphere
These organisms form the first trophic level and capture energy from the Sun.
producers
This pyramid shows the total mass of living organic matter at each trophic level.
biomass pyramid
Food, water, space, and oxygen are examples of these population-limiting elements.
limiting factors
This process breaks down glucose and releases energy, producing carbon dioxide and water.
cellular respiration
This Earth sphere stores carbon in fossil fuels.
geosphere
In a food chain, arrows always point in the direction of this.
energy flow
This pyramid represents the number of individual organisms at each trophic level.
number pyramid
When two species compete for the same limited resource, the population size of one or both species will
decrease
These two substances are the reactants of photosynthesis.
carbon dioxide and water
Burning fossil fuels moves carbon primarily from this sphere to the atmosphere.
geosphere
Only about 10% of energy is transferred between trophic levels because most energy is
used for life processes and lost as heat
Why can number pyramids sometimes appear inverted while energy pyramids never do?
Large producers can support many consumers, but energy always decreases at higher trophic levels.
A wildfire destroys half the vegetation in a habitat. What happens to the carrying capacity of herbivores?
It decreases.
Explain why plants release carbon dioxide even though they perform photosynthesis.
Plants also perform cellular respiration to use stored energy.
During an algal bloom, dissolved carbon dioxide decreases because algae are doing this process.
photosynthesis
Explain why food chains rarely have more than four or five trophic levels.
Energy decreases at each transfer, so there is not enough energy to support additional levels.
In any ecosystem, this pyramid will always maintain a true pyramidal shape.
energy pyramid
Why does reduced decomposition lower an ecosystem’s carrying capacity over time?
Nutrients are not recycled efficiently, limiting plant growth and food availability.
Explain how photosynthesis and respiration together allow carbon to continuously cycle.
Photosynthesis stores carbon in glucose, and respiration releases carbon dioxide back to the atmosphere.
A model shows greater carbon dioxide uptake by plants when atmospheric carbon dioxide levels are higher. What claim does this support?
Higher atmospheric carbon dioxide increases net carbon dioxide consumption by photosynthesis.