Brains of many different species, shown to scale of relative size. See more pictures of brains from many species by clicking here and here.  See also Activity #1.

What Do Nerve Cells Look Like?

Nerve cells are call "neurons." They are like all cells, except that they come in many sizes and types. Their cell membranes form many small branches, both around the cell body and at the ends of long extensions of the cell, called "axons." In this diagram, the part of the cell near the letters is the cell body, which houses the cell nucleus and most of the organelles.  Sometimes it is hard to tell which is extension is the axon and which are just branches on the cell body.

Different types of neurons that occur in brain and spinal cord.

What Do Neurons Do?

• Generate electricity

• Secrete chemicals

Electricity, chemicals, spinal cord

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