Anaphy Nervous System
Anaphy Nervous System
Anaphy Nervous System
FUNCTION:
A. Neurons
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II. Transmission of an Impulse A neuron (nerve cell) has a:
Divisions of the Nervous System Axon – which is a single long cell process
that leaves the cell body at the axon hillock
and conducts sensory signals to the CNS
2 major divisions: and motor signals away from the CNS.
Glial cells
2. Spinal Cord
- supportive cells of the CNS and PNS,
meaning these cells do not conduct - Main communication link between
action potentials. Instead, glial cells brain and the rest of the body
carry out different functions that - Processes information such as
enhance neuron function and maintain reflexes
normal conditions within nervous tissue.
1. Protection of the CNS
NEURONS
- Brain and spinal cord are protected by:
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a) Bone – skull and vertebrae a. Cerebral Hemispheres (Cerebrum)
DISEASE: Meningitis
- Inflammation of the meninges
- Can be caused by an viral , bacterial or
microorganism infection
- Causes headaches, neck stiffness,
confusion, sensitivity to light and sound
- Can be life threatening
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Medulla oblongata - involuntary activities
(breathing, heart rate, blood
pressure).
D. Cerebellum
- “Little brain” inferior to and posterior
to cerebral cortex
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Cerebral edema messages between the body and
- Swelling from the inflammatory the CNS
response - Receives info from the environment
- May compress and kill brain tissue - Transmits commands from CNS to
organs and glands
Cerebrovascular Accident (CVA) - Contains mostly motor and sensory
- Commonly called a stroke neurons
- The result of a blocked or ruptured blood
vessel supplying a region of the brain
Divisions of the PNS
- Brain tissue supplied with oxygen from that
blood source dies
- Loss of some functions or death may result Sensory division
- transmits impulses from sense
Alzheimer’s Disease organs to the central nervous
system
- Progressive degenerative brain disease
- Mostly seen in the elderly, but may begin in
Motor division
middle age
- Structural changes in the brain include ● transmits impulses from the central
abnormal protein deposits and twisted nervous system to the muscles or
fibers within neurons glands
- Victims experience memory loss, irritability, ● Divided into 2 divisions
confusion and ultimately, hallucinations and
- Somatic
death
- Autonomic
Peripheral Nervous System (PNS)
Motor Division
● Sensory Division
Somatic N.S.
● Motor Division
● Regulates activities that are under
- Somatic NS
conscious control
- Autonomic NS ● Example: movement of muscles (wiggle
- Sympathetic toe)
- Parasympathetic ● Involved in reflexes (quick, automatic
response to stimulus)
B. Peripheral Nervous System (PNS)
Autonomic N.S.
- Peripheral Nervous System is made ● Regulates activities that are automatic
up of all the nerves and ganglia or involuntary
● Example: heart rate
(nerve cell bodies) that carry
● Consists of only motor nerves
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● Divided into two divisions
- Sympathetic division
- Parasympathetic division
Sympathetic
- “Fight-or-Flight”
- Takes over to increase activities
- Remember as the “E” division = exercise,
excitement, emergency, and
embarrassment.
Parasympathetic
- “Rest and Digest
- Conserves energy
- Maintains daily necessary body
functions
- Remember as the “D” division =
digestion, defecation, and diuresis
(urination)
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Reflex Pathway