Transport

TRANSPORT


 * **Active Transport**: the pumping of molecules or ions through a membrane against their concentration gradient
 * **Passive Transport**: transport of a substance across a membrane by diffusion

The //cell membrane regulates what enters and leaves the cell// and also //provides protection and support//. The //main function of the cell wall is to provide support and protection for the cell//. Because **diffusion** depends upon random particle movements, substances are able to diffuse across the membrane without requiring the cell to use energy. **Osmosis** is the diffusion of water through a selectively permeable membrane. Osmosis works by moving water across the membrane until equilibrium is reached. //Equilibrium// is when the solute is the same throughout a system. After equilibrium is reached, the two solutes will be //isotonic//, which means "same strengths." During experiements, the majority of concentrated sugar solutions will be either hypertonic, which means "above strength," or hypotonic, which means "below strength." **Facilitated diffusion** is the process of cell membrane proteins //facilitating//, or helping the diffusion of glucose across the membrane.



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