BIOL201 Ch5.2 | Passive Transport | OpenStax Biology

Biology 201 Lecture Video Covering Chapter 5.2 of OpenStax Biology Summary:

Passive transport – Movement of molecules across the membrane by diffusion from high concentration to low concentration. No energy required

Active transport – Movement of molecules across the membrane from an area of low concentration to high concentration. Requires energy.

Diffusion – movement of molecules from an area of high concentration to an area of low concentration.

Solvent is the liquid that something dissolves in. Solute is the solid that dissolves.

Membranes are selectively permeable, only letting small uncharged molecules across.

There are many factors that can influence the rate of diffusion

Facilitated Diffusion uses membrane proteins to help move molecules that wont diffuse easily across the membrane.

Channel proteins are tubes from one side of membrane to the other.

Carrier proteins interact with the substance they transport.

Osmosis is the movement of water across a membrane. Happens when solutes can’t move.

Osmolarity – a solutions total solute concentration.

Tonicity – describes extracellular solutions.


Lecture Presented by Dr. Ben Burrows for the College of Eastern Idaho
Course BIOL 201 Intro Biology