Myasthenia Gravis Autoimmune disease Destroys Ach receptors
Botulism Bacterial toxin Prevents release of ACh
Impulse causes SR to release Ca 2+ Ca 2+ binds to troponin and changes its shape
P i (inorganic phosphate) and ADP released during the power stroke Actin is pulled to middle of sarcomere
New ATP binds to myosin which releases the cross-bridge = relaxation ATPase breaks down ATP into ADP and P i and cycle starts again
Rigor Mortis Without ATP, the sarcomere cannot relax Lasts 72+ hours until muscle fibers decompose (AChE) Acetylcholinesterase – breaks down Ach in synapse Stops impulse to sarcolemma Ca2+ pump 9which needs ATP) moves back to equilibrium Cross-bridges are broken
The next Powerpoint will explain: Where does the ATP come from? What happens when we run out of ATP? Why do I get a cramp in my side when I work out? How are trained athletes’ muscles more efficient?