Define Active Transport Now

In this post, we will not only define active transport but break down how it works, why it is essential for life, and what happens when this system fails. Active transport is the movement of molecules or ions across a cell membrane against their concentration gradient—from an area of lower concentration to an area of higher concentration.

When we think about how things move in nature, we usually think of the path of least resistance. Water flows downhill. Smoke rises into the air. A dropped pen falls to the floor. In biology, this passive movement is called diffusion —particles naturally shifting from an area of high concentration to an area of low concentration until they reach a balanced state. define active transport

Because this movement is "uphill" (moving from low to high), it cannot happen spontaneously. The cell must expend energy, usually in the form of , to power the process. In this post, we will not only define

Think of it like a water wheel. You didn't lift the water to the top of the wheel (primary transport did that). You are just riding the water as it falls back down. Water flows downhill

Enter .