Nervous System: Basic Structure and Function

1. sensory neurons-transmit info from the bodys sensory receptors to the CNS

2. axon terminals-what axons branch out into and end at enlarged tops called neurotransmitters

3. axon- single extension that sends more nerve impulses

4. Neurons- the structural functional units of the nervous system

4.1. Soma(cell body) - central region of the neuron

4.1.1. dendrites-neural extensions that recieve nerve impulses

5. myelin sheath- wrapping around nerve fibers that insulate, protect, and support the neuron

6. nerve-bundle of axons

6.1. ganglion-mass of neural cell bodies

6.1.1. synapse- junction btw two adjacent neurons

7. Brain and Spinal Cord- control center for the Body

8. CNS-integrates incoming info. & determines appropriate responses

8.1. PNS- Peripheral nervous syste- composed of all sensory receptors and nerves that communicate w/ CNS

8.1.1. PNS has 2 divisions- Somatic (controls voluntary skeletal muscle); Anatomic(controls involuntary smooth muscle, cardiac muscle

9. Sympathetic-"Fight or Flight"

9.1. parasympathetic-control rest & digest

10. Glial Cells- act as neural assistantsby providing structural support (entourage)

10.1. Oligodentrocytes- cells that produce the Myelin sheath (CNS)

10.1.1. neuroclemnocytes-cells responsible for producing myelin sheath (PNS)

10.1.1.1. astrocytes- cells that form the blood-brain barrier