Facilitated Diffusion

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What is facilitated diffusion? In membrane, there are protein channels (pores) that allow polar molecules (soluble in water but not soluble in lipids) to move through them. The molecules that move through these channels never come into contact with the hydrophobic layer or the membrane's polar surface because these channels provide a continuous pathway for molecules that are moving through them. In this type of diffusion, like simple diffusion, no energy is consumed. Large and polar molecules require help to pass through the membrane. This help is done by a type of protein called carrier (transport) protein . To pass through the membrane, a molecules binds (temporarily) with carries protein in lipid bilayer and is transported from an area of higher concentration to an area of lower concentration.  Related topics: Simple Diffusion
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Types of wetland-The Knowledge

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Types of wetlands

There are five recognized types of wetlands.(See Wetland)

1.Marine

These are coastal wetlands including coastal lagoons,rocky shores,and coral reefs.

Marine wetland

2.Estuarine

It include deltas,tidal marshes,and mangrove swamps.

Estuarine wetland

 

3.Lacustrine

These wetlands are associated with lakes.

Lacustrine wetland

 

4.Riverine

These wetlands are found along rivers and streams.

Riverine wetland

 

5.Palustrine

These wetlands lack following water,”marshy”,marshes,swamps and bogs.

Palustrine wetland

 

(See Impoetance of wetland)

 

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