Cells and Systems: Going Further

Surface area, diffusion and how the body's systems depend on each other.

8 questions, free, marked as you go with a worked explanation on every one.

What this covers

The questions

  1. A cube-shaped cell measures 2 units on each edge. What is its ratio of surface area to volume?
  2. Using that result, explain why cells stay small rather than growing indefinitely.
  3. A student watches a drop of dye spread through still water. Which statements about diffusion does this demonstrate? Select all that apply.
  4. The small intestine is lined with villi, which are tiny finger-like projections. What is their function?
  5. A person exercises hard. Which describes how the circulatory and respiratory systems work together in response?
  6. A student looks at pond water under a microscope on low power and wants more detail. What is the correct next step?
  7. A cell is measured as 0.05 mm across. How many micrometres is that, given 1 mm = 1000 micrometres?
  8. Which piece of evidence best supports the claim that a newly found organism is multicellular rather than unicellular?

Answer these free