Across
- 3. passes through the lipid bilayer
- 7. requires a channel protein
- 8. where a vesicle fuses with the cell membrane
- 9. the tail part of the phospholipid bilayer.
- 10. the energy used for molecules to get across.
- 12. the head of the membrane
- 14. movement of materials down the concentration gradient
- 15. controls passage of substances.
Down
- 1. proteins that change shape to get molecules through.
- 2. things that help move items in the membrane.
- 4. moves with the flow.
- 5. needs a transport protein to get through.
- 6. going from high to low space
- 11. regulation
- 13. two concentrations are equal.