0
How is an impulse prevented from traveling the wrong way down an axon?
Sadlerfan
The presence of a refractory period caused by the locking of Na channel in the closed position. The happens just after the Na has passed through it and is not influenced by the voltage. This means that that section of the cell cant be depolarised again for a while and so the AP cant go backwardes.
Wiki User
∙ 14y ago
Add your answer:
Earn +20 pts
Which of the following does not factor into the rate of impulse propagation?
Whether or not the impulse begins in the CNS influences the time necessary for a nerve impulse to be transmitted.
Where are action potentials regenerated as they propagate along a myelinated axon?
First at the axon hillock where the neural impulse is initially triggered, and then at the nodes of Ranvier as the impulse continues to travel along the axon.(Note that the impulse travels as electrotonic conduction between the nodes of Ranvier, underneath the glial cells which myelinate the axon.)
A nerve impulse starts at the dendrite then travels to the?
axon
What is the conducting unit of the nerve tissue?
The axon is the conducting part of the neuron. It conducts the impulse from the cell body to the terminals, where ion channels open in response to the impulse, mediators are activated, neurotransmitter crosses synapse and attaches at the post-synaptic membrane, opening the ion channels there and depolarizing the cell, and propagating the impulse towards another cell body via the post-synaptic cell's axon.
A factor that determines the rate of impulse propagation or conduction velocity along an axon?
The speed at which neural impulses are transmitted. Diameter of the axon Degree of myelination of the axon
Does the impulse cross the neuromuscular junction when a muscle contracts?
No, the impulse traveling down the axon ends at the axon terminal but causes the axon terminal to release neurotransmitters. The neurotransmitters diffuse across the synaptic cleft causing the sarcolemma of the muscle to initiate its own impulse.
How are nerve impulses prevented from traveling the wrong way on axon?
On the axon hillock, there is a concentration of sodium channels whose role are to initiate the depolarization and signal transmission allong the axon. Once the all or none threshold is reached, depolarization occurs in a cascade unidirectional along the length of the axon, with potassium channels open just following the sodium-channel mediated depolarization, such that there is no back-propagation of the signal.
Which of the following does not factor into the rate of impulse propagation?
Whether or not the impulse begins in the CNS influences the time necessary for a nerve impulse to be transmitted.
What is nother name for an impulse transmitter?
axon
What carries an impulse away from neuron?
The axon.
What acts as an impulse generator and transmitter?
axon
What sends an impulse to a muscle or gland?
axon
Impulse generator and transmitter?
axon terminal
Microscopic fiber that carries the nervous impulse along a nerve cell?
axon
Where are action potentials regenerated as they propagate along a myelinated axon?
First at the axon hillock where the neural impulse is initially triggered, and then at the nodes of Ranvier as the impulse continues to travel along the axon.(Note that the impulse travels as electrotonic conduction between the nodes of Ranvier, underneath the glial cells which myelinate the axon.)
A nerve impulse starts at the dendrite then travels to the?
axon
What influences the speed of a nerve impulse?
the diameter of an axon
