- Biology Definition: Respiration is a chemical reaction that happens in all living cells. (Both plant cells and animal cells). Respiration is the way that energy is released from glucose so that all the other chemical processes needed for life can happen.
- Normal definition: The action of breathing, also called ventilation.
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The <span>amount of food, habitat, water, and other necessities available in the </span>environment<span>.</span>
A cell which contains cytoplasm, cell membrane and a nucleus
In order for natural selection to take place we must have "variety in a population". This variety of traits is what allows natural selection to "pick" the most favorable traits.