What is EPP and Mepp?
end-plate potential (EPP), chemically induced change in electric potential of the motor end plate, the portion of the muscle-cell membrane that lies opposite the terminal of a nerve fibre at the neuromuscular junction. A single quantum causes only a slight depolarization, called a miniature end-plate potential (MEPP).
What is a MEPP?
Miniature end plate potentials (MEPPs) Miniature end plate potentials are the small (~0.4mV) depolarizations of the postsynaptic terminal caused by the release of a single vesicle into the synaptic cleft.
How does the NMJ work?
The neuromuscular junction (NMJ) is a highly specialized synapse between a motor neuron nerve terminal and its muscle fiber that are responsible for converting electrical impulses generated by the motor neuron into electrical activity in the muscle fibers.
What is the difference between EPP and EPSP?
Size/Effects: An EPSP is not enough to generate an AP in the membrane of the post synaptic neuron. An EPP is large enough to generate an AP in the muscle membrane and subsequently a twitch in the muscle.
What is end plate current?
The macroscopic current resulting from the summed opening of many ion channels is called the end plate current, or EPC. Because the current flowing during the EPC is normally inward, it causes the postsynaptic membrane potential to depolarize.
What is Mepp physiology?
…a slight depolarization, called a miniature end-plate potential (MEPP). These tiny electrical events, called miniature end-plate potentials (MEPPs), or miniature postsynaptic potentials (MPSPs), are caused by the random release of single quanta of neurotransmitter from a resting presynaptic terminal.
What are the 7 steps of neuromuscular junction?
Terms in this set (7)
- An AP travels down the axon. to the axon terminal.
- Electrical gated calcium channels open.
- Calcium causes the vesicles to.
- ACH diffuses across the synaptic cleft.
- ACH binding opens ion channels.
- If the muscle reaches the threshold (-55mv) at the motor end plate.
- ACH is broken down by.
How are EPSPs produced?
EPSPs in living cells are caused chemically. When an active presynaptic cell releases neurotransmitters into the synapse, some of them bind to receptors on the postsynaptic cell. At excitatory synapses, the ion channel typically allows sodium into the cell, generating an excitatory postsynaptic current.
What causes the vesicles inside a neuron to fuse with the plasma membrane?
What causes the vesicles inside a neuron to fuse with the plasma membrane? acetylcholine binding to acetylcholine receptors.
Why are miniature endplate potentials called MEPPs?
Based on these considerations, Katz called these events miniature endplate potentials or MEPPs. They appeared very similar to endplate potentials, but they were only about 0.5 mV in amplitude compared to the 50 mV amplitude of the normal EPP. Katz suggested that MEPPs were due to the spontaneous and random release of ACh.
Is the frequency of MEPPs associated with curare?
An isolated nerve muscle preparation treated with a moderate dose of curare would be associated with a decrease in the (NOTE: there is more than one correct anwer.) A. Frequency of MEPPs This answer is INCORRECT.
How are messages passed from one neuron to another?
Nerve Cell: Dendrites receive messages from other neurons. The message then moves through the axon to the other end of the neuron, then to the tips of the axon and then into the space between neurons. From there the message can move to the next neuron. Neurons pass messages to each other using a special type of electrical signal.
How is the action potential conducted in a neuron?
If the neuron does end up firing, the nerve impulse, or action potential, is conducted down the axon. Structure of a neuron. At one end of the cell body (and indeed, around most of its periphery) are many small, branching protrusions called dendrites.