Active Transport

How do carriers actually function in active transport?

"Carriers" combines with a molecule/ion, which changes their shape, and then transport the molecule/ion across the membrane.

What is needed for active transport to occur?

Energy & carrier "protein" / Protein "Gate"

Active Transport

Requires energy and a carrier protein

What structures in the cell membrane are important in active transport?

Carrier proteins or protein "Gates"

Passive Transport

Does not require energy

Active Transport

Molecules or ions move through the plasma membrane ACCUMULATING either inside the cell (like glucose) or outside the cell (like waste products). Molecules are moving AGAINST the concentration gradient.

Is Water moved directly by active transport? If not, how can cells control H20 movement?

No, Waer Moves PASSIVELY by Osmosis into/out of the cell

Why is active transport necessary?

To Make ATP

What is facilitated diffusion?

Uses carrier proteins/ protein "gates" to help them bridge the bi-layer Both simple and facilitated diffusion move substances down the concentration gradient (High) > (Low) Neither Use Energy.