Primary active transport

Definition

Primary active transport is a process where cells move molecules across the plasma membrane against their concentration gradient using energy directly from ATP. It is essential for maintaining cellular homeostasis and various physiological functions.

5 Must Know Facts For Your Next Test

1. Primary active transport requires direct hydrolysis of ATP to function.
2. The sodium-potassium pump (Na+/K+ pump) is a classic example of primary active transport.
3. This process helps maintain electrochemical gradients essential for nerve impulse transmission and muscle contraction.
4. It involves transmembrane proteins known as pumps or carriers that move ions or molecules.
5. Primary active transport can occur in both prokaryotic and eukaryotic cells.

Review Questions

• What type of energy does primary active transport use to move molecules against their concentration gradient?
• Name an example of a protein involved in primary active transport.
• Why is primary active transport important for cellular functions?

Related terms

Secondary Active Transport: A form of active transport that uses the electrochemical gradient established by primary active transport to move substances.

Sodium-Potassium Pump: A specific type of primary active transporter that exchanges three sodium ions out of the cell for two potassium ions into the cell.

ATP Hydrolysis: The chemical reaction in which ATP is broken down into ADP and inorganic phosphate, releasing energy used in various cellular activities including primary active transport.