Nervous System - Divisions
I. Structural divisions
A. Central nervous system (CNS)
B. Peripheral nervous system (PNS)
II. Functional divisions
A. Somatic Nervous system
B. Autonomic Nervous system
III. Central Nervous System
A. Structures
1. Brain
2. Spinal cord
B. Function: control center for entire nervous system
1. incoming info is integrated and correlated.
Thoughts & emotion are generated and muscles are activated.
IV. Peripheral nervous system (PNS)
A. Structures:
1. Cranial nerves
2. Spinal nerves
B. Function:
1. carry impulses in from receptors and out from cns
a. Sensory (afferent): conducts impulses from body receptors to CNS
b. Motor (efferent): conduct impulses from CNS to Muscles and glands
C. Further Divisions
1. Somatic (soma=body)
a. from cutaneous and special receptors
b. CNS
a. from CNS
b. to skeletal muscles
2. Autonomic (auto=self)
a. from homeostatic receptors in viscera
b. to CNS
a. from CNS
b. to smooth muscle, cardiac and glands
V. Histology
A. structures
1. neuroglia
2. neurons
B. types of neuroglia
1. Astrocytes=support network in CNS
2. oligodendrocytes=produce fatty sheath around CNS axon
3. microglia=engulf and destroy microbes in nervous system
4. ependymocytes=forms continuous lining of ventricles of brain and spinal cord. Assists in circulation of cerebrospinal fluid(CSF)
C. Pathology
1. common source of gliomas(tumors) occur as 40-45% of brain tumors