Davis- AP Bio Unit 2.6-2.8 Review

Passive transport

WITH THE TRANSPORT!!! The net movement of molecules from high concentration to low concentration without the direct input of metabolic energy.

Facilitated Diffusion- Passive Diffusion w/ help

Membrane proteins are required for facilitated diffusion of charged and large polar molecules through a membrane.

Aquaporins

Channels that large amounts of water go through

Channel Proteins

Assist charged ions to go through the membrane

Movment of Ions Across the membrane

may make membranes polarized

Active Transport

AGAINST THE CONCENTRATION! requires direct input of energy to move molecules from regions of low energy to move molecules from regions of low concentration to regions of high concentration.

Endocytosis

Cell takes IN large molecules or substances. The cell’s membrane envelopes the green macromolecule and the large amounts of purple liquid, allowing it to enter in a vesicle. REQURES ENERGY.

The process of endocytosis and exocytosis

Requires energy to move large molecules into and out of cells.

Exocytosis

Cell lets out large molecules or substances.

Endo/Exocytosis requires energy?

True

Internal Vesicles in Exocytosis

Fuse with the plasma membrane and secrete large macromolecules out of the cell.

Active Transport w/ a transport protein

requires ATP and a transport protein (except for active transport via Exo/Endocytosis)

can establish concentration gradients

Active transport

Sodium Potassium pump External

Uses Active transport to push Na+ ions out of the cell (high sodium concentration established outside of the cell)

Sodium Potassium Pump Internal

Uses active transport to push K+ ions into the cell (high potassium concentration inside the cell)

Potential energy

Concentration gradients