Diffusion

• What is diffusion?

  The movement of particles from high to low concentration
• Is simple diffusion an active or passive process?

  Passive process
• How can factors affect the rate of simple diffusion?

  Factors like temperature and concentration gradient
• What is a channel protein?

  A protein that facilitates the transport of particles
• Describe the role of channel proteins in the transport of particles across a cell membrane.

  They allow specific particles to pass through the membrane
• How would changing the number of carrier and channel proteins in a membrane affect the rate of facilitated diffusion?

  Increasing proteins would increase the rate of diffusion
• What is the formula to calculate the gradient of a tangent?

  Gradient = change in y / change in x
• What are the steps to find the rate of diffusion from a graph?

  1. Choose a tangent on the graph
  2. Calculate the gradient of the tangent
  3. Use the gradient to find the rate of diffusion
• What is an important exam tip regarding the rate of diffusion?

  Find the gradient instead of changes in mass
• What type of graph is suitable for finding the rate of diffusion?

  A linear graph
• What are the factors affecting the rate of diffusion?

  • Concentration gradient
  • Temperature
  • Surface area
  • Distance