Active Transport
Active Transport is the term used to describe the processes of moving materials through the cell membrane that requires the use of energy.
There are three main types of Active Transport: The Sodium-Potassium pump, Exocytosis, and Endocytosis.
There are three main types of Active Transport: The Sodium-Potassium pump, Exocytosis, and Endocytosis.
Sodium-Potassium Pump
The Sodium-Potassium Pump is a structure known as a cell-membrane pump that uses energy to transport Sodium and Potassium ions in and out of the cell. There are other varieties of cell membrane pump, however the sodium-potassium pump plays a vital role in maintaining a cell's homeostasis.
The pump is powered by a molecule of ATP. The ATP allows the shape of the pump to change, emptying its contents either into or out of the cell. Below are the steps that the sodium-potassium pump uses to function:
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Endocytosis
Endocytosis is a process by which cells can take in large particles and deposit them into the cell. This is accomplished by forming membrane-bound sacs that pinch off from the cell membrane.
Endocytosis can be used to bring large particles, such as glucose, into a cell. Also, this process can be used by white blood cells to ingest viruses or bacteria and then digest them in their lysosomes. There are two sub-categories of endocytosis: Pinocytosis and Phagocytosis. Pinocytosis brings liquids into the cell while Phagocytosis is responsible for transporting large particles or other solids into the cell.
Endocytosis can be used to bring large particles, such as glucose, into a cell. Also, this process can be used by white blood cells to ingest viruses or bacteria and then digest them in their lysosomes. There are two sub-categories of endocytosis: Pinocytosis and Phagocytosis. Pinocytosis brings liquids into the cell while Phagocytosis is responsible for transporting large particles or other solids into the cell.
Exocytosis
Exocytosis is very similar to endoxytosis except that it deposits materials from inside the cell on the outside instead of the other way around. Vesicles are formed in the Golgi Bodies, filled with materials to be sent outside the cell, and then fuse with the cell membrane and release their contents outside of the cell.