Homeostasis and Cellular Transport

Passive Transport

passive transport does not require energy to move particles across the membrane.
examples include osmosis, diffusion, and facilitated diffusion
this type of transport happens when molecules move with the concentration gradient, from areas of high concentration to low concentration.

Active Transport

Active transport requires energy in the form of ATP and a transport protein - such as a sodium-potassium pump. This type of transport happens when the molecules being transported are going against the concentration gradient, from areas of low concentration to areas of high concentration.

​diffusion

Diffusion occurs when dissolved molecules move from high to low concentration without assistance from a channel protein, they just slip through the membrane.
This type of transport does not require ATP.

​Facilitated Diffusion

Diffusion occurs when dissolved molecules move from high to low concentration with assistance from a channel protein, they cannot just slip through the membrane.
This type of transport does not require ATP.

osmosis

Diffusion of water molecules across a semipermeable membrane from an area of low solute concentration to an area of high solute concentration.
This type of transport does not require ATP.

​Active transport

Active transport occurs when dissolved molecules move from an area of low solute concentration to high solute concentration.
This type of transport requires ATP and channel proteins.

​Endocytosis

Endocytosis happens when the cell uses its membrane to surround molecules and bring them into the cell.
This type of transport requires ATP.

​Exocytosis

Exocytosis happens when the cell uses vesicles to surround molecules and remove them from the cell.
This type of transport requires ATP.