Diffusion Activity Questions

Part A:

  1. What chemical added to the agar allowed the agar blocks to become colorless in the presence of an acid?
  2. Describe what you observed in the three agar blocks at the end of the activity.
  3. What causes the HCl to move into the agar?
  4. The strength of the HCl solutions increased in steps of 10 times (from 0.05% to 0.5% to 5%). Did the distance the HCl penetrated the agar increase proportionally? Explain.
  5. Speculate how the results might change if the agar blocks in the HCl solution were heated. Explain your reasoning.
  6. What was the objective of Part A of this activity?

Part B:

  1. Which cube had the smallest pink area? Which had the largest?
  2. Which cube had the smallest surface area to volume ratio? Which had the largest?
  3. What was the objective of Part B of this activity?
  4. Explain how a cell relies upon diffusion.
  5. All the cell's nutrients and respiration gases must travel through the cell surface. Discuss why this makes the surface area to volume ratio important.
  6. Are elephant cells larger than mouse cells? Explain.