Active Transport

Active Transport Occurs when cells move materials from one side of membrane to another going against the concentration gradient. Always requires energy. There are four forms of active transport we need to explore: Endocytosis Pinocytosis/Phagocytosis Exocytosis

Endocytosis The process of taking material into the cell by means of infolding* of the cell membrane. *infolding means to fold inward.

Endocytosis type 1: Pinocytosis Pinocytosis is the taking up of liquids from the environment into the cell. In ancient Greek “pino” means to drink.

Endocytosis type 2: Phagocytosis Phagocytosis is when an extension of cytoplasm is used to surround a particle and package it within a vacuole. In ancient Greek “phago” means to devour. Phagocytosis “Cell Eating”

Exocytosis The process of releasing materials from inside the cell using energy.

Sodium-Potassium Pump

Okay, Let Drake show us what we need to know…

The long and short is: Three sodium ions bind with the protein pump inside the cell. The carrier protein then gets energy from ATP and changes shape. It then pumps the three sodium ions out of the cell. At that point, two potassium ions from outside the cell bind to the protein pump. The potassium ions are then transported into the cell, and the process repeats. The sodium-potassium pump is found in the plasma membrane of almost every human cell and is common to all cellular life.

Let’s look again.

Another approach.