Net diffusion will always occur. Net diffusion always occurs from a region of higher concentration to a region f lower concentration and the distances covered are very small. Study with Quizlet and memorize flashcards containing terms like Which of these statements describes what occurs in facilitated diffusion? -Facilitated diffusion requires energy from the cell to drive a concentration gradient. In the human body, it is essential for gas exchange in the lungs, where oxygen diffuses from the alveoli into the bloodstream due to a higher oxygen concentration in the lungs than in the blood. What factors are required for net movement of a substance to occur by facilitated diffusion? a concentration gradient a plasma membrane a transport protein All of these choices are correct. e) The equilibrium potential for K+ (EK) becomes more positive. Fick's first law can be used to derive his second law, which in turn is identical to the diffusion equation. A concentration gradient is the difference in concentration of a substance between two areas, which drives diffusion or osmosis. a concentration gradient C. Osmosis occurs until the concentration gradient of water goes to zero or until the hydrostatic pressure of the water balances the osmotic pressure. Molecules or particles must have different sizes B. bwsv tablnc fabgoph gqnda mgz bqh fdu svp zbnoxx jkcnir