Are cells that react and act in the process of receiving and transmitting information by signaling.
They are an important function of the nervous system.
They are found:
Neurons themselves can differ greatly – some allow for touch, visual, light, smell, sound
and many others.
Neurons in limbs receive stimuli and transfer or send the signal to the spinal cord and to the brain.
Chemical ions are the basic mechanism of response. Ions are released and “uptake” during stimuli.Â Ions cause an “electrical charge” that extends along the neuron.Â This charge is similar to dominos falling in a pattern and along a shaped arrangement.
The anatomy of a typical neuron is as follows:
Nucleus Â Â
Â Â -Â Â Production of RNA
Â Â -Â Â Production of Proteins
Â Â -Â Are branch-like prominences from the neuron
Â Â -Â They function to receive stimuli from an adjacent neuron
Â Â -Â They appear to collect the information and pass it to the axon in the appropriate
speed and intensity.
Â Â -Â Â This is referred to as the cell body of a neuron
Â Â -Â Â It houses the nucleus of the neuron
Â Â -Â Â Is a long cord or fiber that allows the conduction of impulses
Â Â -Â Â The longest axon is the “sciatic nerve” – which runs from the spine
to the big toe of each foot
Â Â -Â Â Is sheathed or surrounded by myelin
Â Â -Â Â A layer that surrounds the axon
Â Â -Â Â Schwann cells surround those of the Peripheral nervous system
Â Â -Â Â Oligodendrocytes surround those of the Central nervous system
Â Â -Â Â Is the end of the neuron
Â Â -Â Â Action potentials or electrical impulses are generated here
Â Â -Â Â Chemicals or “neurotransmitters” are essential
Types or Classifications of neurons:
Â Â -Â Dendrite and axon from same portion – only one axon
Â Â -Â Cell body is typical in central aspect of neuron
Â Â -Â Found in spinal cord and brain
Â Â -Â Single axon
Â Â -Â Axon on one side and dendrite on other
Â Â -Â Found in eye, smell, and hearing locals
Â Â -Â Single axon
Â Â -Â Multi-dendrites
Â Â -Â Found in brain
Several seperate but similar neuron types are seen:
1.) Anterior horn – found in spinal cord
2.) Basket Cells – found in cerebellum
3.) Betz Cells – are vey large neurons that allow for motor movement
4.) Granule Cells – a type of Golgi II neurons
5.) Medium Spiny Nerurons – found in corpus striatum
6.) Purkinje Cells – found in cerebellum
7.) Pyramidal Cells – a type of Golgi I neurons
7.) Renshaw Cells – linke to alpha motor neurons