Final answer:
Diffusion is the passive movement of molecules from an area of high concentration to an area of low concentration. In living organisms, diffusion is important for obtaining energy and removing wastes.
Step-by-step explanation:
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration, in order to achieve equilibrium. It is a passive transport mechanism that does not require energy expenditure. In living organisms, diffusion plays a crucial role in the movement of various substances such as gases (like oxygen and carbon dioxide) and small molecules across cell membranes.
For example, during respiration, oxygen diffuses from the lungs into the bloodstream and then from the blood into body cells, where it is used for energy production. Conversely, carbon dioxide, a waste product of cellular respiration, diffuses out of cells into the bloodstream and is eventually eliminated from the body through exhalation.
Similarly, in plants, diffusion aids in the absorption of carbon dioxide from the atmosphere and the release of oxygen produced during photosynthesis.
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