0
The electrical impulse in a nerve cell begins when ions move through the cells surface through ion channels.
The nerve impulse.
A nerve impulse is a wave of excitation that quickly travels within the surface of a neurone (nerve cell). This nerve impulse usually travels on certain parts of the nerve cell: on a dendrite or an axon. Within a neurone the first event depends on the type of 'nerve impulse'; there are two important types:
1- nerve impulses generated at dendrites
2- self propagating nerve impulses (action potentials) that travel along the axon
Nerve impulses generated at dendrites.
Dendrites feed into the 'cell body' (soma) of a neurone. Nerve impulses that are generated in these dendrites travel toward the cell body.
A sequence of events occur at the surface of a dendrite when the nerve impulse is sparked. The first event is transduction; this involves the transformation of one form of energy outside the dendrite into electrical energy within the dendrite.
Nerve impulses that travel along axons.
Nerve cells often have many dendrites but often only have a single axon. The essential difference between the two parts of the nerve cell is:
- in dendrites electrical impulses travel TOWARDS the cell body of the neurone
- in the axon the electrical impulses travel AWAY from the cell body of the neurone
The nerve impulse that travels along an axon begins at the 'base of the axon', where the cell body and axon merge. This site is called the 'axon hillock' and is found to be the site where the first event in the formation of a nerve impulse actually occurs. Again, the first event is transduction at the axon hillock.
Conclusion; the first event.
For both of the cases above, and for virtually any other case, the nerve impulse begins with a process of transduction. The electrical nerve impulse begins once the first 'ions' leave or enter the nerve cell. Usually sodium ions enter, sometimes calcium ions are the firs to enter, sometimes potassium ions are the first to leave.
Wiki User
∙ 14y ago
Add your answer:
Earn +20 pts
Where does a nerve impulse start?
A nerve impulse starts at the dendrite
The duration of a nerve impulse is approximately?
A nerve impulse is approximately 1 millisecond.
What is the relay station for nerve impulses?
There is no relay station in nerve impulse conduction.
What is the message sent down the neuron called?
What they relay is whether of not they were 'on' or 'off' and how often; and this occurs as an action potential firing frequency. There is no message in the sense that neurons might pass on complex messages, like an email for instance; or store memories of events and facts. No one neuron can do anything like that. It takes many neurons working together to achieve this.
A nerve impulse starts at the dendrite then travels to the?
axon
What is the sequence of events that correlates to the sequence of events of a nerve impulse?
2,1,3,4
What is quicker a nerve impulse or a hormone?
nerve impulse
Where does a nerve impulse start?
A nerve impulse starts at the dendrite
Which travels quicker through the body a nerve impulse or a hormons?
a nerve impulse
The neurotransmitters of a neutron enable a nerve impulse to do what?
they transport the nerve impulse through the synapses (:
Is ventricular systole responsible for nerve impulse?
no ventricular diastole is responsible for nerve impulse
The duration of a nerve impulse is approximately?
A nerve impulse is approximately 1 millisecond.
How does a nerve impulse follow all or nothing principle?
How does a nerve impulse follow the all-or-nothing principle???
What pathway does a nerve impulse follow after initiated into a receptor?
nerve my a$$ nerve
Is an action potential necessary for a nerve impulse to occur?
Yes, an action potential is needed for a nerve impulse to occur.
Is a action potential necessary for a nerve impulse to occur?
Yes, an action potential is needed for a nerve impulse to occur.
What is a nerve impule transmitted by axons?
It is called a nerve impulse.
