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I'm a bit confused on this question....
(problem 2 on passage 1 in chapter 3 bio)
The conduction velocity of action potentials along smooth muscle fiber is low because activation of:
A Potassium channels is slow
B sodium channels is slow
C calcium channels is slow
D Magnesium channels is slow
"C is correct, calcium channels is slow. As in cardiac muscle, an inward calcium current is an important component of the action potential in smooth muscle. We are told that the conduction velocity is low along smooth muscle fiber. It is logical to assume that the conduction velocity of action potentials along GI smooth muscle fibers is slow because activation of the calcium channels is slow. This question was just designed to make one think about theof calcium in the conduction velocity of an action potential of smooth muscle. The correct choice is C."
1. So my question is about the difference between muscle contraction and action potentials. For action potentials down a muscle fiber, would slow-opening sodium channels cause a slow velocity of an action potential? I know that calcium is needed for contraction, but the question is action about the action potential itself. Are they referring to the calcium that is needed for acetylcholine release the NMJ?
2. Also separate question, but the muscle cell is the myofibril right? and a bunch of muscle cells/ myofibrils make up the muscle fiber
Thanks for your help!
(problem 2 on passage 1 in chapter 3 bio)
The conduction velocity of action potentials along smooth muscle fiber is low because activation of:
A Potassium channels is slow
B sodium channels is slow
C calcium channels is slow
D Magnesium channels is slow
"C is correct, calcium channels is slow. As in cardiac muscle, an inward calcium current is an important component of the action potential in smooth muscle. We are told that the conduction velocity is low along smooth muscle fiber. It is logical to assume that the conduction velocity of action potentials along GI smooth muscle fibers is slow because activation of the calcium channels is slow. This question was just designed to make one think about theof calcium in the conduction velocity of an action potential of smooth muscle. The correct choice is C."
1. So my question is about the difference between muscle contraction and action potentials. For action potentials down a muscle fiber, would slow-opening sodium channels cause a slow velocity of an action potential? I know that calcium is needed for contraction, but the question is action about the action potential itself. Are they referring to the calcium that is needed for acetylcholine release the NMJ?
2. Also separate question, but the muscle cell is the myofibril right? and a bunch of muscle cells/ myofibrils make up the muscle fiber
Thanks for your help!