A neuron also known as nerve cell is an electrically excitable cell that takes up, processes and transmits information through electrical and chemical signals. It is one of the basic elements of the nervous system. In order that a human being can react to his environment, neurons transport stimuli. The stimulation, for example the burning of the finger at a candle flame, is transported by the ascending neurons to the central nervous system and in return, the descending neurons stimulate the arm in order to remove the finger from the candle.
A simple structure designed for a complex task. A typical neuron is divided into three parts: the cell body, the dendrites and the axon. The cell body green color , the center of the neuron, extends its processes called the axon and the dendrites to other cells.
Dendrites typically branch profusely, getting thinner with each branching blue color. The axon is thin but can reach enormous distances violet color. To make a comparable scale, the diameter of a neuron is about the tenth size of the diameter of a human hair. The neuron is the basic working unit of the brain, a specialized cell designed to transmit information to other nerve cells, muscle, or gland cells.
Neurons are cells within the nervous system that transmit information to other nerve cells, muscle, or gland cells. Most neurons have a cell body, an axon, and dendrites.
The cell body contains the nucleus and cytoplasm. The axon extends from the cell body and often gives rise to many smaller branches before ending at nerve terminals. Dendrites extend from the neuron cell body and receive messages from other neurons.
Synapses are the contact points where one neuron communicates with another. The dendrites are covered with synapses formed by the ends of axons from other neurons.
Illustration by Lydia V. The brain is what it is because of the structural and functional properties of interconnected neurons.
The mammalian brain contains between million and billion neurons, depending on the species. Each mammalian neuron consists of a cell body , dendrites , and an axon. There are different types of neurons , both in the brain and the spinal cord. They are generally divided according to where they orginate, where they project to and which neurotransmitters they use. Axon — The long, thin structure in which action potentials are generated; the transmitting part of the neuron.
After initiation, action potentials travel down axons to cause release of neurotransmitter. Dendrite — The receiving part of the neuron. Dendrites receive synaptic inputs from axons, with the sum total of dendritic inputs determining whether the neuron will fire an action potential. Spine — The small protrusions found on dendrites that are, for many synapses, the postsynaptic contact site.
Action potential — Brief electrical event typically generated in the axon that signals the neuron as 'active'. An action potential travels the length of the axon and causes release of neurotransmitter into the synapse. The action potential and consequent transmitter release allow the neuron to communicate with other neurons. Help QBI research Give now. QBI newsletters Subscribe.
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