Biology 30 Anatomy of the Nervous System - Bow Valley College

Anatomy of the Nervous System
Hard copies, other resources and learner support are
available in the LRS on the fourth floor of Bow Valley
College
The Anatomy of the Nervous System
I. General Layout of the Nervous System
A. The Major Divisions of the Nervous System
two main divisions:
a. Central Nervous System (CNS)
consists of the brain and the spinal cord
b. Peripheral Nervous System (PNS)
divided into two subsystems
1. Somatic Nervous System (SNS)
composed of afferent nerves - carry sensory input from the sensory
receptors.
composed, also of efferent nerves that carry signals from the
central nervous system to the effectors, such as skeletal muscles to
cause movement
2. Autonomic Nervous System (ANS)
regulates the internal environment
consists of afferent and efferent nerves
is under "automatic" control
divided into:
Sympathetic Nervous System
⇒ nerves that stimulate, organize and mobilize energy
⇒ mobilizes that body energy for action
⇒ voluntarynervous system
Parasympathetic Nervous System
⇒ acts to conserve energy
⇒ slows the body "down"
⇒ involuntary nervous system
Central Nervous System
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Anatomy of the Nervous System
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Anatomy of the Nervous System
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