Passive Transport- The movement of materials across the cell membrane without using cellular energy.

Diffusion- Process by which particles move from an area of higher concentration to an area of lower concentration.

Moves substances across the cell membrane.

Facilitated Diffusion- Process in which molecules that cannot directly diffuse across the membrane pass through special protein channels.

Two Types of Passive TransportDiffusion Osmosis

Diffusion ExampleClose your eyes..

Imagine your home on a Sunday morning and the smell of bacon being cooked on the stove awakens you. How did the smell of bacon travel through the house?

The energy sends droplets of fat into the air, Brownian Motion and Kinetic energy cause the fat droplets to collide and disperse until equilibrium is reached.

OsmosisAquaporins- Cells

that contain water channel proteins, that allow water to pass right through them.

Osmosis- the diffusion of water through a selectively permeable membrane. Molecules move from an area of higher concentration to an area of lower concentration.

Osmosis moves water molecules across a cell, not solute molecules!

Does not require energy!

How it works!Isotonic- Reached when

both sides of the membrane reach the same concentration of sugar and water.

Hypertonic- Solution with the greater concentration of solutes.

Hypotonic- Solution with the lesser concentration of solutes.

Water can pass through, but sugar cannot!

Osmotic Pressure- Force produced by the net movement of water out of or into a cell.

Active TransportMovement of

materials against a concentration difference.

Ex: Sodium-potassium pump.

REQUIRES ENERGY!

Molecular TransportProtein pump-

Energy from ATP is used to pump small ions across the cell membrane. Bind on one side of the membrane and release them on the other.

Transport of these ions by protein molecules is vital to the production of electrochemical impulses along the nerve cell.

Bulk TransportEndocytosis-

Process of taking material into the cell by means of infoldings, or pockets, of the cell membrane. Phagocytosis- type of

endocytosis that is responsible for engulfing damaged cells.

REQUIRES ENERGY SO THEREFORE IS ACTIVE TRANSPORT!

Exocytosis- A vesicle fuses with the cell membrane and forces material to be expelled of the cell.