For a fish to be buoyant, or float, it must displace less water or the same amount of water as its own body mass. ... Many fish use swim bladders to help them with quick depth changes. These bladders fill with air to help fish rise or release air so fish can sink, often in conjunction with forward movement.
<em>Living things... oh yes. </em>
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<em>The answer here would be "has a heart". Every living thing doesn't necessarily have a heart. Trees and plants do not have hearts, yet they are alive. (Some scientists believe that plants have pulses, though. No heart, but a pulse! Odd, isn't it?)</em>
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<em>I hope this answers your question.</em>
<em>-Toremi</em>
This really depends on the ecosystem, as each ecosystem may respond differently.
Explanation:
How an ecosystem responds is going to depend on the ecosystem, as each ecosystem may respond differently, and also on the extent and magnitude of the natural disaster. It takes ecosystems a long time to return to semi-normal conditions it can take up to 200 years for a forest to regrow after a huge fire. and that doesn't include the animals displaced/killed in the disaster.
Answer: There is no following statements. But a controlled experiment is a scientific test that is directly manipulated by a scientist, in order to test a single variable at a time. The variable being tested is the independent variable, and is adjusted to see the effects on the system being studied.