the PM of cardiac The cardiac drugs ouabain &digitalis work by partially inhibiting the action of the Na+/+pump in muscle cells. Explain why this might result in stronger cardiac contractions and also why an overdose o become a deadly poison? these drugs could Proton pumps driven by ATP hydrolysis are found in the PM of plants, fungi and many bacteria. What is the ro H+ ATPase pumps in these cells? Can pumping out protons establish a proton electrochemical gradient across their P The membrane of cellular lysosomes also contains a proton pump driven by ATP hydrolysis. Does it pump proton into or out of the lumen of the lysosome? Why? Proton pumps are not always driven by ATP hydrolysis. Give at least two examples. Channel Proteins Are channel proteins involved with the active or passive movement of particles/solute across the membrane? By far, most channel proteins have small pores. Name 2 exceptions and state where they are found What is an “aquaporin”? Where might it be found and what’s its role? Over 100 different types of “small pore” channel proteins are known. What is the major thing passing through these channel proteins? What are the 2 the major differences between an “aqueous pore” and an “ion channel”?