Active transport

Definition

Active transport is the movement of molecules across a cell membrane from a region of lower concentration to a region of higher concentration, using energy in the form of ATP. It is essential for maintaining cellular homeostasis and enabling various physiological processes.

5 Must Know Facts For Your Next Test

1. Active transport requires energy input, usually in the form of ATP.
2. It moves substances against their concentration gradient, from low to high concentration.
3. The sodium-potassium pump is a prime example of active transport in animal cells.
4. Carrier proteins or pumps are involved in active transport mechanisms.
5. Active transport helps maintain electrochemical gradients necessary for functions like nerve impulse transmission.

Review Questions

• What type of energy is required for active transport?
• How does active transport differ from passive transport?
• Can you name an example of a protein that facilitates active transport?

Related terms

Passive Transport: The movement of molecules across a cell membrane without the use of energy, moving from high to low concentration.

Sodium-Potassium Pump: A type of active transport that moves three sodium ions out and two potassium ions into the cell against their concentration gradients.

ATP (Adenosine Triphosphate): The primary energy carrier in cells, used to power various cellular processes including active transport.