10. Describe the relationships between the following terms: concentration gradient, voltage, and potential energy. 11. Explain what physiological process generates Resting Membrane Potential and what mechanism exists to maintain it. 12. Define ion pump and give at least one example. 13. Describe the process of co-transport. 14. Compare and contrast exocytosis and endocytosis and give an example of each. 15. Compare and contrast phagocytosis, pinocytosis, and receptor-mediated endocytosis. .