Nervous Tissue

What are the types of nerve cells?

There are 2 major types of nerve cells:

• Neurons function - conducts impulses around the body

10% of nerve cells

• Neuroglia function - support, insulate, and protect neurons

90% of nerve cells

What is the structure of a neuron?

 Neurons have different structures but all have a main cell body with processes extending outward. The cell body contains the nucleus, cytoplasm, and organelles. 

Processes are divided into:

• Dendrites - brings impulses towards the cell body

• Axons - sends impulses away from the cell body

  • End in axon terminals, which release neurotransmitters to pass the impulse to the next neuron

What are the types of neurons?

Neurons are classified by the number of processes extending from the cell body.

• Unipolar neurons - one process

• Bipolar neurons - two processes

• Multipolar neurons - have many processes 

Neurons can also be classified by their function.

• Afferent neurons - carry impulses towards the CNS

• Efferent neurons - carry impulses away from the CNS

• Interneurons - connect afferent and efferent neurons

Summary: Neurons make up 10% of the nervous system tissue, but they are the essential cells for carrying impulses around the body. The impulses pass through the processes and into the cell body. Neurons can be classified by the number of processes they have or by their function.