What is motor endplate?
The specialized postsynaptic region of a muscle cell. The motor endplate is immediately across the synaptic cleft from the presynaptic axon terminal. Among its anatomical specializations are junctional folds which harbor a high density of cholinergic receptors.
What is the main function of motor end plate?
neuromuscular junction …of muscle fibre called the end plate. Embedded in the end plate are thousands of receptors, which are long protein molecules that form channels through the membrane. Upon stimulation by a nerve impulse, the terminal releases the chemical neurotransmitter acetylcholine from synaptic vesicles.
What is a motor end plate quizlet?
– Motor end plate—the muscle fiber membrane in which the sarcolemma is tightly folded and where nuclei and mitochondria are abundant. – Synaptic cleft—space between the synaptic end bulb and motor end plate.
What does the motor end plate contain?
The terminal branch of each motor neuron axon forms a large synapse called the motor end plate or neuromuscular junction on the muscle surface (see Fig. 17.9). These nerve endings are filled with synaptic vesicles containing the neurotransmitter acetylcholine.
What is motor end plate fatigue?
Persistent firing of action potentials to maintain muscle contraction results in acetylcholine depletion at the motor end plate, initiating the process of central fatigue. This is determined by the innervated muscle fiber’s conduction velocity and subsequent variations in the action potential waveform shape.
What is found at the motor end plate during excitation?
The motor end-plate is the location of the ACh-receptors in the muscle fiber sarcolemma. When ACh molecules are released, they diffuse across a minute space called the synaptic cleft and bind to the receptors.
Where is the motor end plate of the muscle located?
Motor end plate There is one neuromuscular junction associated with each muscle fiber, and it is typically located near the middle of the fiber. This means that the motor end plate will also be located near the midpoint of the muscle fiber.
What kind of receptors are found at the motor end plate?
The acetylcholine receptors on the motor end plate are concentrated along the shoulders of the folds defining secondary clefts in the sarcolemma. The receptors are made up of five subunit proteins forming a cylinder with a central pore ion channel. Each receptor unit has two sites for acetylcholine binding.
What is the correlation of the motor end plate with the skeletal muscles explain?
Motor End-Plate and Innervation At the NMJ, the axon terminal releases ACh. The motor end-plate is the location of the ACh-receptors in the muscle fiber sarcolemma. When ACh molecules are released, they diffuse across a minute space called the synaptic cleft and bind to the receptors.
When acetylcholine binds to its receptor on the motor end plate?
Depolarization of the motor end plate occurs when both receptors bind acetylcholine, causing a conformational change in the channel complex, opening it to the inward flow of positive ions (Figure 19-2).
What are motor end plates associated with?
The motor end-plate is the connection between the motor nerve and the skeletal muscle cell. Its function is to transmit the electrical signal (= action potential) from the nerve cell to the muscle cell. This is the stimulus that will make the skeletal cell contract.
What is the neurotransmitter released at the motor end plate?
Acetylcholine, often abbreviated as ACh, is a neurotransmitter released by motor neurons that binds to receptors in the motor end-plate. What happens at motor end plate? Mechanism of action. Botulinum toxin’s effects occur at the motor end plate.
What does motor endplate mean?
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
What is the typical speed of moving plate?
The majority of the research shows that the plates move at the average rate of between approximately 0.60 cm/yr to 10 cm/yr. Some sources state that in the North Atlantic, the rate of movement is only about 1 cm (about 0.4 in) per year, while in the Pacific it amounts to more than 4 cm (almost 2 in) annually, while others say that plates, in general, travel from 5 to 10 cm/yr.