The Neuron

Neurona specialized cell transmitting nerve impulses; a nerve cell.
GliaNon Neuronal cells that protect the neurons in the CNS and form myelin.
CNSThis consists of the brain and the spinal cord and plays a major role in the coordination of many bodily functions.
MyelinA insulating layer around nerves.
Axonsis a nerve fibre that protudes from the neuron that conducts impulses away from the cell body
Dendritestransfer nerve signals to the soma.
SomaThe cell body of the neuron

In the brain there are two main groups of cells: Neurons and glia. Although most people have only heard of neurons, there actually tenfoldmore glia in the brain than neurons.

This is because neurons are vital in the functioning of the brain, whereas glias main function is to package and protect the neurons.

Trying to observe neurons in the past has been impossible, as observing them requires a microscope due to their small size. To add to the difficulty the jelly like texture of the neurons and the uniform cream colour makes observing even under a microscope difficult so it requires preparation.

Santiago found that after immersing the tissues in formaldehyde to harden the neurons making them possible to slice into thin layers, and staining them with Golgi stain. The neuron became visable.

Golgi stained neuron

Images obtained from using the Golgi stain showed that neurons had two main parts. A central region that contains the nucleus and thin tubes that branch out.

The tubes that spread out from the centre are neurites and are split into 2 groups axons and dendrites.

The body of the neuron typically has one axon coming out from it, with varying lengths of over a metre. Whereas dendrites are much shorter mainly under 2mm long. The inside of the neuron has a liquid called cytosol, a salty solution.

Dendrites are tree like branched structures. They are covered in 1000s of synapses, and the membranes that surround them are 75% involved in synaptic connections. In general their function is to receive a signal from other neurons and pass it on to to the cell body. 

So in essence neurons transmit electrical signals which are received at the dendrites and then transmitted to the soma and leave through the axons.

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