Anatomy And Physiology

ANATOMY AND PHYSIOLOGY
Full year work

,Function of the Nervous System:

1. Gather Information (Sensory Input):
o Monitors changes occurring both inside and outside the body.
2. Process Information (Integration):
o Analyzes and interprets the sensory data collected.
3. Respond to Information (Motor Output):
o Initiates a response to the processed information.




Structure of the Nervous System:

1. Central Nervous System (CNS):
o Includes the brain and spinal cord.
2. Peripheral Nervous System (PNS):
o Comprises nerves extending from the brain and spinal cord.




Functional Classification:

1. Sensory Division:
o Responsible for transmitting sensory information to the CNS.
2. Motor Division:
o Carries motor commands from the CNS to muscles and glands.




Central Nervous System (CNS):

1. Organs:
o Brain and spinal cord.
2. Function:
o Acts as the command center for processing and integrating sensory
information.
o Interprets sensory input and issues outgoing instructions.




Peripheral Nervous System (PNS):

1. Organs:
o Nerves that extend from the brain and spinal cord.
▪ Spinal Nerves: Carry information to and from the spinal cord.
▪ Cranial Nerves: Carry information to and from the brain.
2. Function:
o Serves as a communication network, connecting the CNS to the rest of the
body.

, Functional Classification

Nervous System




Central Nervous System Peripheral
Nervous System
Organs: Brain & Spinal cord Organ: Nerves

Function: Process information
Function: Communication




Sensory Division Motor Division
Carries info to the CNS Carries info away from
CNS




Autonomic Nervous System Somatic Nervous
System
Involuntary
Voluntary
Cardiac and Smooth muscle Skeletal muscle




Sympathetic Nervous System Parasympathetic Nervous
System

, Smooth muscle
Cardiac muscle
Exocrine glands
Some endocrine glands


Nervous Tissue: Neurons

• Neurons = nerve cells.
• Specialized cells designed to transmit electrical messages (impulses).

Major Regions of Neurons:

1. Cell Body:
o Contains the nucleus and acts as the metabolic center of the cell.
2. Processes:
o Fibers that extend from the cell body.




Processes Extending from the Cell Body:

1. Dendrites:
o Conduct impulses toward the cell body.
2. Axons:
o Carry impulses away from the cell body.
o Terminate in axon terminals, which contain vesicles filled with
neurotransmitters, separated from the next neuron by a synapse.
3. Myelin Sheath:
o A whitish, fatty insulating layer.
o Produced by Schwann cells.
o Nodes of Ranvier: Gaps in the myelin sheath that aid in impulse
transmission.



Functional Classification of Neurons:

1. Sensory Neurons:
o Transmit impulses from sensory receptors to the CNS.
o Include proprioceptors, which detect tension in muscles and joints.
2. Motor Neurons:
o Carry impulses from the CNS to muscles, organs, or glands.
3. Interneurons:
o Found within neural pathways in the CNS.
o Connect sensory neurons to motor neurons.