Flashcards in Ch 23 Practice Deck (23)
Organisms that undergo photosynthesis make food which other organisms consume; a photosynthetic organism is a _____.
In the carbon cycle, organisms return carbon dioxide to the atmosphere through the process of cellular ______.
Food chains generally consist of only three or four steps due to the loss of ______ between trophic levels.
A heterotroph that breaks down organic matter into inorganic nutrients that are recycled in the environment is called a ______.
Nitrogen can be a nutrient that limits growth in an ecosystem because the plentiful nitrogen in the atmosphere is:
In a form that is unusable to most organisms
An organism that cannot synthesize organic compounds from inorganic substances and therefore must consume organic food is called a(n) ______, or consumer.
______ are underground rock layers that hold water and are recharged by seepage from rain or melting snow.
What factors determine an organism's niche in an ecosystem?
• How an organism gets its food
• What an organism eats
• How the organism interacts with other populations in the same community
A(n) ______ is an organism that can use energy and inorganic nutrients to produce organic nutrients.
Phosphates are required by organisms to build which of the following molecules?
• Nucleic acids
The air, land, and water that contains living organisms on Earth is called the
IN aquatic ecosystems, the exchange of carbon dioxide with the atmosphere is indirect because carbon dioxide from the atmosphere enters the water as ______ ions.
Tertiary consumers can also be called top
1st trophic level
2nd trophic level
3rd trophic level
Ecological ______ can sometimes be used to depict large energy losses between successive trophic levels.
What chemicals are reactants for the process of photosynthesis?
• Carbon dioxide
Aquatic ecosystems are divided into two groups: those composed of ______ water (rivers, lakes, and ponds) and those composed of ______ water (marine ecosystems).
Certain cyanobacteria, some free-living bacteria in the soil, and bacteris within root nodules are capable of
In what ways are inorganic nutrients made available to producers>
• Physical processes, such as the weathering of rocks
• The action of decomposers
Most of the organic nutrients used by all organisms are produced by