Nerves Flashcards
What is the action potential of a nerve?
It creates a signal through the nerve to make quick communications throughout the body.
What is the threshold of excitation of the nerve? What is the value of this threshold?
It’s the threshold that must be reached to create a action potential. -55mV.
What is an “all or nothing” response?
It is the response to the threshold of excitation being reached, which creates a action potential within the nerve.
What ions are located within the neuron?
Potassium ions (K+) and negatively charged proteins.
What ions are located outside of the neuron?
Sodium ions (Na+) and Chloride ions (Cl-) .
What is the charge or the resting phase?
≈ -70mV
What is the charge of the peak of the rising phase?
≈ +50mV
What happens in hyperpolarization?
The potassium gates close and the membrane within the neuron becomes extra polarized, (extra negative), and the sodium/postassium pumps allow ions to flow through, which compensates for the extra negativity within the neuron.
What are sodium/potassium pumps?
They are pumps that utilize active transport to move ions in and out of the membrane. It uses 1 ATP for every 3 Na+ and 2 K+.
What does myelin do to the signal of the neuron?
It allows the signal of the neuron to move quicker, by insulating the axon.
What is a dendrite?
They recieve the singals from other neurons. They are essentially brances that are connected to the nerve cell body.
What is an axon?
The axon is the main branch that sends the signal towards the effector. It is in between the nerve cell body and the axon terminals*.
*The presynatptic neuron
What is a Node of Ranvier?
The Node of Ranvier is the gap between myelin along the axon. The space contains sodium and potassium gates.
What is a Schwann Cell?
It is the cell that produces the myelin around the axon.
What is Myelin?
Myelin is an insulating protein produced by the Schwann Cells. It allows for the signal from a neuron to travel faster.
What is the postsynaptic membrane?
Or the postsynaptic neuron
It is the part of the neuron that comes after the synaptic cleft*. It receives signals via neurotransmitters (vesicles) that attach to the receptors.
*Synaptic cleft = Synaptic gap
What is the synaptic knob?
Or the the presynaptic neuron..
It is the part of the neuron that comes before the synaptic cleft*. It contains thousands of neurotransmitters that allow for an action potential to be communicated to other neurons.
*Synaptic cleft = Synaptic gap
What is an excitatory neurotransmitter?
It is a neurotransmitter that promotes a nerve impulse within the dendrite by allowing sodium to flow.
What is a inhibitory neurotransmitter?
It is a neurotransmitter that hinders a nerve impulse within the dendrite by hyperpolarizing the neuron.
What effect does Dopamine do to your body and to your nerves?
It allows your nerves to communicate more freely and gives you a “feel-good” effect. It is secreted within the CNS.
What effect does Seritonine have on your body and on your nerves?
It controles your mood and helps you think. It has an inhibitory effect on your nerves.
What effect does glutamate have on your body and on your nerves?
It
