What are the different types of membrane transport? what are the three classes of transport?

The most prominent types of membrane transport are 1) Passive 2) Active 3) Endocytosis/exocytosis.

Explanation:

1) Passive Transport-

It can be further classified into-

a. Diffusion- In diffusion small molecules or lipid soluble molecules pass through the membrane of phospholipid from their high concentration to the areas of their lower concentration.

b. Osmosis- In this process water molecules move through a membrane which is selectively permeable, from their higher concentration to their lower concentration.

c. Facilitated diffusion- In this process molecules take help of the protein channels to move across the membrane.

2) Active Transport- In this process the cell uses its energy(ATP) to move the substance across against their concentration gradient.

3) Endocytosis and Exocytosis( For movement of large particles)-

The cells take up the substance from outside by a process called Endocytosis. Endocytosis can be further classified into-

Phagocyytosis- if the substance taken up is solid

Pinocytosis- If the substance taken up is fluid

Exocytosis- the cell excretes by exocytosis

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.