Membrane proteins called pumps use energy to move hydrogen ions to one side of the membrane. Which term describes the difference between the
numbers of hydrogen ions on opposite sides of the membrane?
O A. Concentration gradient
O B. Equilibrium
O C. lon concentration
O D. Homeostasis

the supermassive black hole is in the middle of the galaxy.

photosynthesis makes the glucose that is used in cellular respiration to make atp. the glucose is then turned back into carbon dioxide, which is used in photosynthesis. while water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.