Nerons And Nerve Impulse Flashcards
(11 cards)
Which part of the neuron receives an impulse?
The dendrites receive impulses.
In what direction do impulses travel through a neuron?
Impulses travel from the dendrite end to the axon.
What is the function of the myelin sheath?
The myelin sheath insulates the axon so impulses can travel faster.
What is the synapse?
The synapse is the area where an impulse moves from one neuron to another.
What is released from the terminal branches?
Neurotransmitters
What is the state of the cell membrane of a neuron during the resting potential?
The neuron is polarized. It is positively charged on the outside and negatively charged on the inside.
In terms of a nerve impulse, what is the threshold?
The threshold in the minimum amount of stimulation the neuron needs to send an impulse.
How does the cell membrane of a nerve cell become polarized?
The sodium-potassium pump moves sodium ions out of the cell and potassium ions in. Potassium ions are able to move out of the cell by diffusion but the sodium ions are blocked from moving into the cell.
What is depolarization?
During an impulse the channels are opened to sodium ions and they rush into the cell, changing the polarity of the membrane to positive on the inside and negative on the outside.
What is the function of neurotransmitters?
Neurotransmitters are chemicals that travel across the synapse cleft to the next neuron.
What are the three types of neurons?
Sensory neuron, motor neuron and interneuron.
