The Nervous System
Amanda Skipworth
Danielle Slagle
Jack Harrington
Period: 6
What is the Nervous System?


Consists of neurons, nerves, nerve impulses, and neuroglial cells

Nerves: bundles of axons

Nerve impulses: information in electrochemical form

Neuroglial cells: provides physical support, insulation, and nutrients for neurons
Divided into the central nervous system (CNS) and the peripheral
nervous system (PNS)

CNS consists of brain and spinal cord

PNS consists of other body parts
What Are the Functions of the Nervous
System?

Sensory functions: internal and external changes

Integrative functions: decision maker

Motor functions: carries out function
What is a Neuron?

Structural and functional units

Transmits information in electrochemical form (nerve impulses)

Every neuron includes a cell body, dendrites, and an axon
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Cell body: rounded area with two extensions
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Dendrites: receive electrochemical messages
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Axons: send information in nerve impulse form
How are Neurons Classified?
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Neurons differ in structure, size, and shape of their cell bodies

Neurons also vary in function such as:
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
Sensory

Interneurons

Motor
3 major groups
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Multipolar
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Bipolar

Unipolar
Sensory Neurons
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Afferent neurons
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Carry impulses to PNS
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Dendrites have specialized tips

Changes inside or outside body trigger sensory nerves

Most unipolar; some bipolar
Interneurons

Also known as association or internuncial neurons

Lie within the brain/spinal cord
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Multipolar neurons

Link to other neurons

Transmits impulses from one part of the brain/spinal cord to another

Directs incoming sensory impulses
Motor Neurons

Efferent neurons

Multipolar

Carry nerve impulses out of the brain/spinal cord to effectors

Stimulates muscles and glands

Causes reactions
What is a Synapse?

The junction between any two communicating neurons

Not in direct physical contact separated by synaptic cleft
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Synaptic transmission is a one way process, like a phone call

Neurotransmitters carry out synaptic transmission
Frontal Lobe

Location: Frontal and upper area of the cortex

Function: Carries out higher mental processes

Thinking
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Decision making

Planning

Emotions
Parietal Lobe
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Location: Upper, back part of the cortex
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Function: Processes sensory information

Taste

Temperature

Touch
Occipital Lobe
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Location: Bottom, back part of the cortex
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Function: Responsible for processing visual information from the eyes
Temporal Lobe
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Location: Bottom middle part of the cortex; behind the temples
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Function: Responsible for processing auditory information
Cerebellum
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Location: Lower area of the brain

Function: Responsible for balance and coordination of the body
Medulla Oblongata

Location: Lower part of the brain stem
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Function: Carries out and regulates life sustaining functions

Breathing

Swallowing

Heart rate
The Difference Between CNS and PNS
PNS
CNS

Brain and spinal cord

Sensory and motor pathways

Involuntary actions

Voluntary actions

Processes information

Carries information to and from
CNS and other cells
What is the Autonomic Nervous System?

Portion of PNS that functions independently without a conscious effort

Controls


Smooth muscles

Cardiac muscle

Glands
Regulates

Heart rate
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Blood pressure

Breathing rate
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Body temperature
What is the Difference Between
Sympathetic and Parasympathetic?
Sympathetic

Fight or flight

Controls body’s responses to a
threat

Sympathetic nerve fibers leave
spinal cord
Parasympathetic

Rest and recover

Controls homeostasis

Begin in the brainstem
What are the Human’s Somatic Senses?

Touch and pressure


Temperature


Free ends of sensory nerve fibers
Two sets of free nerve endings
Pain

Two main types of pain fibers

Acute

Chronic
Relationship Between Sense of Taste and
Smell

Chemicals in food are detected by taste buds

Odorants are detected by sensory neurons located in the nose

Olfactory information passes to the orbital cortex,

The combination of odor and taste information helps create the perception of
flavor
Works Cited

"Activity: Nervous Energy." Nervous Energy. 1 Jan. 2002. Web. 18 Mar. 2015.

"BrainFacts.org." Taste and Smell. 1 Apr. 2012. Web. 18 Mar. 2015.

"Led around by Our Noses." The Telegraph. Telegraph Media Group. Web. 18
Mar. 2015.

"Neuron to Glia Synapses on Axons?" Pure Pedantry. Science Blogs, 6 Mar.
2007. Web. 18 Mar. 2015.

What’s the Difference between a Food’s Taste and Its Flavor?" Web. 18 Mar.
2015.