Download What are Neurons

What are Neurons?
 a nerve cell is the basic building block of the central nervous system
 neurons are specialized to transmit information throughout the body
 there are approximately 100 billion neurons in the human brain alone
 neurons, as highly specialized nerve cells, communicate information in both chemical and
electrical forms (an electro-chemical process)
 There are thee basic types:

Sensory neurons carry information from the sensory receptor cells throughout the body
to the brain.

Motor neurons transmit information from the brain to the muscles of the body.

Interneurons are responsible for communicating information between different neurons
in the body.
About Neurons
 there is some evidence that new neurons can be created (neurogenesis), especially in the
hippocampus, but this is a very new area of research. Thousands are produced each week,
but most of these die within weeks. Previously it had been believed that we are born with a
set number of neurons.

Even if not many neurons are reproduced, research has shown that new connections between
existing neurons form throughout life

Neurons have a membrane that is designed to sends information to other cells. The axon and
dendrites are specialized structures designed to transmit and receive information.

The connections between neurons are known as a synapse. Neurons release chemicals
known as neurotransmitters into these synapses to communicate with other neurons.
Neat to Know

The longest axon in a human being’s motor neuron can be just over a meter, from the
base of the spine to the toes.

The longest axon in a human being’s sensory neuron is approximately 1.5 meters, from
the toes to the dorsal column

Giraffes can have axons several meters in length (spanning the length of their neck)

Squids were critical in learning about the functioning of neurons: they have a particular
relatively large axon at 0.5mm to 1mm thickness, several centimetres in length; scientists
could isolate the squid neuron and keep it functioning in salt water for about 12 hours.
A signal propagating down an axon to
the cell body and dendrites of the next
cell.