What is an end plate current?
The macroscopic current resulting from the summed opening of many ion channels is called the end plate current, or EPC. In particular, the identity of the ions that are carrying the current can be determined by knowing the membrane potential at which no current flows in response to transmitter binding.
What is end plate potential caused by?
EPP are caused mostly by the binding of acetylcholine to receptors in the postsynaptic membrane. There are two different kinds of acetylcholine receptors: nicotinic and muscarinic. These receptors are slow and therefore are unable to measure a miniature end plate potential (MEPP).
Is end plate potential an action potential?
The end-plate potential is a graded potential (it is not all-or-none) that propagates electrotonically to the neighboring patch of muscle fiber membrane where it initiates an action potential on the muscle much like it does on unmyelinated nerves.
What is EPP and Mepp?
epp = end-plate potential (general term is epsp for excitatory post-synaptic. potential) mepp = miniature end-plate potential (general term is mepsp) = quantal unit. Quantal hypothesis: Single, spontaneous quantal events (mepps) represent the building blocks of for the synaptic potentials evoked by stimulation (epps).
What is end point potential?
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. The action potential will then stimulate the muscle cell to contract.
Is end plate potential inhibitory?
Generally, it is known as an excitatory postsynaptic potential (EPSP). Curare blocks the endplate potential because it is a competitive inhibitor of acetylcholine (ACh), the transmitter released at the presynaptic terminal.
Where is end plate potential?
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.
What is end plate neuromuscular junction?
Neuromuscular junctions, also called motor end plates, are specialised chemical synapses formed at the sites where the terminal branches of the axon of a motor neuron contact a target muscle cell. The muscle cell plasma membrane underlying the synaptic cleft forms the postsynaptic membrane.
What is receptor end plate?
The endplate AChR belongs to a large superfamily of neurotransmitter receptors, called Cys-loop receptors, and has served as an exemplar receptor for probing fundamental structures and mechanisms that underlie fast synaptic transmission in the central and peripheral nervous systems.
What is an end plate potential quizlet?
End-plate potential (EPP) is the postsynaptic potential induced at the neuromuscular junction by the opening of the nicotinic acetylcholine receptor. -The Acetylcholine receptor is a mixed-cation channel (simultaneous Na+ and K+).
What happens when an action potential reaches motor end plates?
What happens when an action potential reaches motor end plates? A. Calcium ions are absorbed by the muscle fibres. Action potential is passed to the neuron.
How does end plate potential differ from action potential?
The end plate potentials are generated in the muscle cells. Action potential refers to a change in the electrical potential, which is associated with the transmission of impulses along the membrane of a nerve cell or muscle cell. The three main stages of an action potential are the depolarization, repolarization, and refractory period.
What is the function of a motor end plate?
The motor end plate is the basic component of a nerve-muscle junction, which functions as a synapse with chemical transmission; a stimulus is transmitted from nerve to muscle by means of a mediator, and it contracts.
What is the end plate of a muscle?
End plate potentials (EPPs) are the voltages which cause depolarization of skeletal muscle fibers caused by neurotransmitters binding to the postsynaptic membrane in the neuromuscular junction. They are called “end plates” because the postsynaptic terminals of muscle fibers have a large, saucer-like appearance.
What is a motor end plate?
motor end plate – the flattened end of a motor neuron that transmits neural impulses to a muscle. endplate, end-plate. effector – a nerve fiber that terminates on a muscle or gland and stimulates contraction or secretion.