The Basic Neuron and axon terminal Functions
Norepinephrine
A neurotransmitter involved in arousal, as well as in learning and mood regulation
Acetylcholine
A neurotransmitter that enables learning and memory and also triggers muscle contraction
synaptic cleft
At a chemical synapse, one neuron releases neurotransmitter molecules into a small space (the synaptic cleft) that is adjacent to another neuron. the synaptic cleft helps to decode the message. When the electrical signal reaches the presynaptic ending, it is translated into a chemical message that then diffuses across the synaptic cleft to the postsynaptic cell.
Dendrites
Branchlike parts of a neuron that are specialized to receive information.
Nodes of Ranvier
a gap in the myelin sheath of a nerve, between adjacent Schwann cells. The nodes of Ranvier allow for ions to diffuse in and out of the neuron, propagating the electrical signal down the axon. Since the nodes are spaced out, they allow for saltatory conduction, where the signal rapidly jumps from node to node.
Synapse
a junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter.The function of this is to transfer electric activity (information) from one cell to another.
Axon
nerve fiber, is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action potentials, away from the nerve cell body.
Synaptic vesicles
store various neurotransmitters that are released at the synapse.Vesicles are essential for propagating nerve impulses between neurons and are constantly recreated by the cell.
Synaptic end bulbs
The end bulb contains synaptic vesicles which are filled with a neurotransmitter substance. When a nerve impulse travels down the axon and reaches the end bulb the neurotransmitter is released into a small space, the synaptic cleft.The function of a synaptic knob is to change the action potential that is carried by axons into a chemical message.
Cell Body (soma) include the nucleus
The spherical part of the neuron that contains the nucleus. The cell body connects to the dendrites, which bring information to the neuron, and the axon, which sends information to other neurons.
Axon terminals
The very end of a branch of a nerve's axon, a long slender nerve fiber that conducts electrical signals to a nerve synapse (the gap between nerve cells). The axonal terminals are specialized to release the neurotransmitters of the presynaptic cell.
Myelin sheath
an insulating layer, or sheath that forms around nerves, including those in the brain and spinal cord. It is made up of protein and fatty substances. The main purpose of myelin is to increase the speed at which electrical impulses propagate along the myelinated fiber.