Download Active Transport Notes

Concept:
Key Point
Active Transport
Is energy needed? Why?

Details

Energy in the form of ATP is
needed because substances are
being moved AGAINST their
concentration gradient (from low to high)

This pump has specially shaped “holders” for ions of
Na+ and K+. Using ENERGY, it moves Na+ and
K+ AGAINST the concentration gradient.

3 Na+ ions are pumped out of the cell, and 2 K+
ions are pumped into the cell.

Na+ and K+ are important ions in our body that help
keep our cells healthy.

Occurs when the cell membranes forms a vesicle
(like an envelope) around an item that needs to
ENTER the cell.

Endocytosis is used for transporting molecules
INTO the cell that are too large for facilitated
diffusion.

Occurs when the cell membranes forms a vesicle
(like an envelope) around an item that needs to
EXIT the cell.

Exocytosis is used for transporting molecules OUT
OF the cell that are too large for facilitated diffusion.

The receptor can cause membrane channels to open.

The receptor may cause the formation of a second
messenger that will have an effect in another part of
the cytoplasm. (sends a message like a walkie-talkie)

The receptor can act as an enzyme (causes a reaction
to occur or effects the permeability of the
membrane).
YES! It does require energy
Several types of active transport
1. Sodium – Potassium Pump
3 Na+
2 K+
2. Endocytosis
3. Exocytosis
4. Receptor Proteins