Neurons are often said to be large, active cells. Is this true?

Dear tteam1234-ga,

The human body is made up of trillions of cells. Cells of the nervous
system, called nerve cells or neurons, are specialized to carry
"messages" through an electrochemical process. The human brain has
about 100 billion neurons. To learn how neurons carry messages, read
about the action potential.

Neurons come in many different shapes and sizes. Some of the smallest
neurons have cell bodies that are only 4 microns wide. Some of the
biggest neurons have cell bodies that are 100 microns wide. (Remember
that 1 micron is equal to one thousandth of a millimeter!!).

Neurons are similar to other cells in the body because:

Neurons are surrounded by a cell membrane. 
Neurons have a nucleus that contains genes. 
Neurons contain cytoplasm, mitochondria and other "organelles". 
Neurons carry out basic cellular processes such as protein synthesis
and energy production.

However, neurons differ from other cells in the body because:

Neurons have specialized extensions called dendrites and axons.
Dendrites bring information to the cell body and axons take
information away from the cell body.
Neurons communicate with each other through an electrochemical process. 
Neurons contain some specialized structures (for example, synapses)
and chemicals (for example, neurotransmitters).

For further details go to:
faculty.washington.edu/chudler/cells.html 

Other interesting sites are:

www.enchantedlearning.com/ subjects/anatomy/brain/Neuron.shtml 

catalog.nucleusinc.com/generateexhibit.php?ID=6472 

patentcad.medicalillustration.com/generateexhibit.
php?ID=6472&ExhibitKeywordsRaw=&TL=16353&A=...

See the following link for more psychology information:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=2496126370&ssPageName=STRK:MESE:IT

cheyuta1939 talks about the diameter of the cell bodies, but not the
length.  In a human neurons can be up to a meter in length (from the
foot to the bottom of the spinal chord).  On the other hand they can
also be a few microns in length as well.  In the case of the squid
giant nerve, I single cell can be removed from the animal and seen
easily with the naked eye.  The important idea is not to confuse a
neuron with a nerve.  A nerve is a bundle of neurons, these are often
quite large and again can be seen easily with the naked eye.

Metabolically, neurons are not that different from any other cell in
the body, but they carry a voltage difference across their membrane
that can be manipulated to carry an "electric current" down the length
of the cell.  The only other cell type that can carry this current on
its membrane is the muscle cell.

Hope this supplements cheyuta's comment