When is facilitated diffusion necessary?

Facilitated diffusion is necessary when cell membranes prevents a substance from diffusing on its own.

Facilitated diffusion is a type of passive transport that involves movement of solute materials down the concentration gradient.

Further Explanation;Transport in living organismsPlants and animals use various processes to transport materials from one point to another.There are classified as either passive transport or active transport.Passive transportIt is a type of transport that does not involve the use of energy to aid movement of substances in living organisms.Passive transport involves free movement of substances and through special types of transporters or carriers.Types of passive transport includes; simple diffusion, facilitated diffusion, osmosis, and mass flow among others.Active transport  It is a type of transport in living organisms that involves movement of substances against a concentration gradient and involves use of energy in form of ATP to aid transport of substances.Types of passive transportFacilitated diffusionFacilitated diffusion is a type of passive transport which involves the diffusion of solutes by use of transport proteins in the plasma membrane.Facilitated diffusion uses transport proteins to transport solutes down their concentration gradient. Osmosis  Osmosis is a special diffusion that involves the movement of water molecules from a region where they are highly concentrated to a region where they are lowly concentrated through a semipermeable membrane.It may also refer to the movement of water molecules from a region of low particle concentration to a region of a high particle concentration.Diffusion  Diffusion is a type of passive transport that involves movement of particles from a region of high concentration to a region of low concentration.Diffusion involves movement of molecules of substances other than water.

Keywords: Passive transport, Diffusion, Osmosis, Passive transport

Learn more about:  Passive transport; Active transport: Osmosis: Diffusion:

Level: High school  

Subject: Biology

Topic: Transport in living organisms

Sub-topic: Passive transport

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