Diffusion

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Diffusion

Diffusion is the process by which particles spread out from an area of higher concentration to an area of lower concentration.

In cells, substances move in and out across the cell membrane by diffusion, allowing essential exchanges to take place.

Examples of substances that move by diffusion include:

Oxygen and carbon dioxide during gas exchange.
Urea, a waste product, which diffuses from cells into the blood plasma for removal by the kidneys.

Diffusion

Factors affecting the rate of diffusion

Concentration Gradient: The greater the difference in concentration between two areas, the faster the rate of diffusion.
Temperature: Higher temperatures increase the movement of particles, speeding up diffusion.
Surface Area of the Membrane: A larger surface area allows more particles to diffuse at once, increasing the rate.
Distance: The shorter the distance particles have to travel, the faster the diffusion rate.

By understanding these factors, we can predict how efficiently substances like gases and waste products move in and out of cells, helping them function properly.

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