In an ecosystem, the amount of material stays about the ________________.
Everything in an ________________ can be used over and over again.
In an ecosystem, the consumers eat the producers and use _____________ from them to grow.
Producers need ________________, which consumers give off.
During phtosynthesis, producers use light energy to change carbon dioxide and _____________ into sugar and water.
The opposite of photosynthesis is __________.
sugar + oxygen
The chemical equation for photosynthesis is energy from sunlight + carbon dioxide + water = ______________ + _____________.
energy + water
The chemical equation for respiration is: sugar + oxygen = carbon dioxide + _____ + ______.
photosynthesis and respiration
two processes that are part of the carbon dioxide-oxygen cycle
Another important cycle is the ____________ cycle.
_____________ is part of all proteins
_____________ are the materials cells use for growth and repair.
stays the same
Nitrogen is used over and over so that the amount of nitrogen _____________.
Nearly 80% of the air we breathe is nitrogen ____________.
Most organisms need nitrogen gas to change into nitrogen ________________.
lightening and bacteria
2 ways to change nitrogen gas into nitrogen compounds
When animals eat plants and then are eaten by another animal, the usable nitrogen flows through the ____________.
When decomposers break down wastes and dead organisms, they return nitrogen compounds to the _____________.
Some bacteria that live in the soil can then change nitrogen compounds back into ___________.
The ____________ is the cycle that changes nitrogen gas into nitrogen compounds and the back into nitrogen gas.
The _____________ is when water evaporates from the ground, condensation forms in clouds, and precipitation falls to the ground.
living and nonliving
Water cycles through the __________ and ______________ parts of an ecosystem so no new water is needed.