Question

Draw a graph of what happens during the action potentials of an SA node call and the action potentialsbof a cardiac muscle cell. Your x-axis should be time in seconds and your y-axis should be membrane potential in millivolts. Be sure to indicate on the graph which ion channels are open at which times and which ions are moving in which direction. inlcude a paragraph description of the similarities and differences between the two types of action potentials.

Answer 1

1. Action potential of SA NODE and cardiac muscle
2. Differences of both action potentials of S a node and cardiac muscle

3. S a node	Cardiac muscle
   Duration of action potential is 200 to 300 ms	Duration of action potential is 3 to 5 ms
   The initiation of action potential Depolarisation is by calcium channels opening	Depolarisation of action potential is by sodium channel opening
   No prolong of action potential	Channels prolong action potential by influx