Put the steps involved in muscle contraction in the correct chronological order after an action potential arrives at the motor neuron axon terminal:

medical student was doing research in a laboratory that studiesthe neuromuscular junction. Which of the following events atthe junction are listed in correct sequential order?A. Motor neuron action potential, acetylcholine release, Na+entry at the endplateB. Ca2+ entry into the motor nerve terminal, Na+ entry at theendplate, muscle fiber action potentialC. Na+ entry at the endplate, acetylcholine release, muscle fiberaction potentialD. Motor neuron action potential, Na+ entry at the endplate,formation of an endplate potentialE. Ca2+ entry into the motor nerve terminal, acetylcholinerelease, Na+ entry at the endplate

Place the steps of the muscle action potential in the appropriate order.Rank the options below.An action potential arrives at the presynaptic terminal.An action potential arrives at the presynaptic terminal. open choices for rankingCalcium ions enter the presynaptic terminal.Calcium ions enter the presynaptic terminal. open choices for rankingACh binds to and opens ligand-gated Na+ channels on the postsynaptic membrane.ACh binds to and opens ligand-gated Na+ channels on the postsynaptic membrane. open choices for rankingVoltage-gated Ca2+ channels in the presynaptic membrane open.Voltage-gated Ca2+ channels in the presynaptic membrane open. open choices for rankingNa+ enters the postsynaptic cell.Na+ enters the postsynaptic cell. open choices for rankingThe enzyme acetylcholinesterase removes acetylcholine from the synaptic cleft.The enzyme acetylcholinesterase removes acetylcholine from the synaptic cleft. open choices for rankingThe neurotransmitter acetylcholine (ACh) is released from pre-synaptic vesicles.The neurotransmitter acetylcholine (ACh) is released from pre-synaptic vesicles. open choices for rankingACh unbinds from the ligand-gated Na+ channels, which then close.ACh unbinds from the ligand-gated Na+ channels, which then close. open choices for rankingPostsynaptic membrane begins to depolarize.Postsynaptic membrane begins to depolarize. open choices for rankingACh is released and diffuses into the synaptic cleft.ACh is released and diffuses into the synaptic cleft. open choices for rankingIf depolarization passes threshold, an action potential is generated along the postsynaptic membrane.If depolarization passes threshold, an action potential is generated along the postsynaptic membrane. open choices for ranking

The sequence of events that converts action potentials in a muscle fibre to a contraction is known as

n regards to excitation-contraction coupling, what does the action potential propagate along when it reaches the muscle?

Arrange these action potential events in their proper sequence: (1) The neuron is stimulated at the dendrites (2) K+ gates open (3) The neuron is in a polarized “resting” state (4) Na+ gates open (5) The cell is fully depolarized (6) The cell is fully repolarized a. 1, 2, 4, 3, 5, 6b. 3, 1, 4, 5, 2, 6c. 4, 6, 2, 1, 5, 3d. 1, 4, 2, 6, 5, 3