diffusion

• diffusion?

  The movement of particles from an area of high concentration to an area of low concentration.
• is simple diffusion active or passive?

  passive
• what factors affect diffusion?

  temperature, concentration gradient
• diffusion across a membrane through protein channels is called facilitated diffusion
• does facilitated diffusion require energy?

  no
• does diffusion move up or down a conc. gradient?

  Down
• what are the requirements of the particles that move by diffusion?

  small, non-polar
• what factors affect rate of diffusion?

  temperature, surface area of membrane, thickness of membrane, concentration gradient
• is facilitated diffusion active or passive?

  Passive
• what affects the rate of facilitated diffusion that doesn't affect the rate of simple diffusion?

  number of channel proteins or carrier proteins