Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can explain how the size, polarity and charge of a molecule decide whether it needs a transport protein. (Guide: “Structure decides the route”; Practice Q1)
- I can define facilitated diffusion and explain why it is passive even though it uses a protein. (Guide: “Structure decides the route”; Practice Q2)
- I can compare channel proteins and carrier proteins, and draw a labelled diagram of each. (Guide: Figure 1)
- I can explain why Na⁺ and K⁺ need channel proteins, and how their movement can polarize a membrane. (Guide: “Ions, channels and polarized membranes”; Practice Q5)
- I can explain what aquaporins do and why water still crosses slowly without them. (Guide: “Aquaporins”; Practice Q4)
Calculation and skills
- I can calculate percentage changes from transport data and use them to show that a rate is levelling off. (Guide: Worked example 1; Practice Q4, Q7)
- I can read a rate–concentration graph and tell simple diffusion from facilitated diffusion. (Guide: Figure 2; Practice Q7)
- I can split a rate into a bilayer part and a protein part, and predict what changes when the number of proteins changes. (Practice Q3, Q4)
Reasoning
- I can explain why the rate of facilitated diffusion has a maximum, and what limits the rate at low and at high concentration. (Guide: Worked example 1)
- I can predict the effect of blocking a channel or carrier on a cell, and follow it to the whole organism. (Guide: Worked example 2; Practice Q6)
- I can explain why net ion movement can stop before concentrations are equal. (Practice Q5)
- I can explain why facilitated diffusion can never raise the concentration of an uncharged solute above that on the other side. (Practice Q6)
All ticked? Move on to Topic 2.7, Tonicity and Osmoregulation, or return to the course roadmap.