Symporter

Definition

A symporter is a type of membrane transport protein that moves two different molecules or ions across a cell membrane in the same direction. It plays a crucial role in active transport, utilizing the energy from one molecule moving down its concentration gradient to move another molecule against its gradient.

5 Must Know Facts For Your Next Test

1. Symporters are essential for the uptake of nutrients and ions in cells.
2. They rely on the electrochemical gradient of one substance to drive the transport of another.
3. Common examples include the sodium-glucose transport protein found in intestinal cells.
4. Symporters are distinct from antiporters, which move substances in opposite directions.
5. The function of symporters is vital for maintaining cellular homeostasis and nutrient absorption.

Review Questions

• What is the primary function of a symporter?
• How does a symporter differ from an antiporter?
• Can you give an example of a symporter and explain its role in cellular processes?

Related terms

Antiporter: A type of membrane transport protein that moves two different molecules or ions across a cell membrane in opposite directions.

Electrochemical Gradient: The combined effect of an ion's concentration gradient and electrical charge difference across a membrane.

Active Transport: The movement of molecules or ions across a cell membrane against their concentration gradient, requiring energy input.