Download Nervous System - Anderson School District One

Nervous System
Functions of the
Nervous System
1.Receives information from outside and
inside the body
2. Responds to the information
3. Helps the body maintain homeostasis
School House Rock Telegraph
Video
Vocabulary to Know
• Homeostasis
– Maintaining steady conditions inside an
organism, despite changes in its
environment
2 parts of the nervous system
The Nervous
System – 2 Parts
• I. peripheral nervous system - all
the nerves outside the
CNS.
• II. central nervous system –
- brain and spinal cord.
I. Peripheral Nervous System Connects body to brain &
spinal cord
Made of:
Neurons / Nerve Cells
– Basic functioning
units of the nervous
system
Draw in
notebook
to label as
discussed.
Nerve Cells /
Nerve Tissue
Nerve Cells
• Axons carry impulses away from
the cell body.
Nerve Cells
• Dendrites They grow when you learn.
Synapses
Synapse - A small space between
neurons
Neurotransmitters – Chemical
messages that
jump the synapse.
Impulse - A message carried by a neuron.
An impulse moves in only one direction across
a synapse - from an axon to the dendrites or
cell body of another neuron.
Types of neurons
Sensory neurons – Picks up messages
from the senses.
Inter-neurons – In spinal cord or brain
and transfers messages to the motor neurons.
Motor neurons - Sends impulses to
muscles.
II. The Central Nervous System
– Brain and Spinal Cord
Pushing the Limits – Brain
43
The Central Nervous System – Brain and Spinal Cord
The Brain
Brain Recognition
The Brain
• Coordinates body activities
• Made up of approximately 100
billion neurons
• Divided into three major parts–the cerebrum
–the cerebellum
–the brain stem.
Cerebrum
The Central Nervous System – Brain and Spinal Cord
Cerebrum - Largest part of the brain.
- Interprets senses, stores
memory.
Interactive
The Central Nervous System – Brain and Spinal Cord
Cerebellum - Maintains balance, muscle
movement, & coordination
http://www.harcourtschool.com/activity/brain/brain.html
Cerebellum
The Central Nervous System – Brain and Spinal Cord
Brain Stem - At the base of the brain
(Medulla) - - controls your involuntary
functions.
Brain Stem
Memory Games
• Short Term Memory Test
• Short Term Memory Picture Test
The Central Nervous System – Brain and Spinal
Cord
Spinal Cord - The link
between your brain and
peripheral nervous system
The
Peripheral
Nervous
System
Your brain
and spinal
Somatic
cord are
and
connected
Autonomic
to the rest
Systems
of your
The
body by
peripheral
the
nervous
peripheral
system
has
nervous
two
major
system.
divisions.
The PNS
is made up
somatic
of 12 pairs
system
of nerves
controls
from your
voluntary
brain It
actions.
called
is
made up
cranial
of
the
nerves, and
cranial
and 31
spinal
pairs from
nerves
that
your
go
from
spinal
the
cord called
central
spinal
nervous
nerves. to
system
Spinal
your
nerves are
skeletal
made up of
muscles.
bundles of
The
sensory
autonomic
and motor
system
neurons
controls
bound
involuntary
together by
actionsconnective
those
not
tissue. For
under
this
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These
same
the
two
nervous
time.
divisions,
Some
system.
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along
with
Make
contain
the
central
a
brochure
only
nervous
outlining
sensory
system,
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make
medical
and
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some
advances.
contain
body's
only motor
nervous
neurons,
system.
but most
nerves
contain
both types
of neurons.
Reflexes
• reflex -an involuntary, automatic
response to a stimulus.
• You can’t
control reflexes
because they
occur before
you know what
has happened.
Reaction Time Activity
Reflexes
• A reflex allows the body to respond without
having to think about what action to take.
• Reflex responses are controlled in your
spinal cord, not in your brain.
How the Body Works
Senses
• Sight
• Tasting
• Hearing
• Touching
• Smelling
How do you see?
Cornea – shields the
pupil and iris.
Pupil – an opening that
controls light needed to
see.
Iris – smooth muscle that
controls pupil.
Lens - Focuses the
image on the retina.
Retina – cells in the back
of the eye that send
nerve impulses to the
brain.
Brain and Eye Working Together
Optical Illusions
More Illusions
What are “Optical Illusions?”
• http://www.michaelbach.de/ot/
Hearing
The Outer Ear
• Intercepts sound waves and funnels them
down the ear canal to the middle ear.
Middle Ear
• hammer, anvil, and stirrup – sound waves
change to vibrations.
The Inner Ear
• 1. cochlea - a fluid-filled structure
like a snail’s shell with hair-like
structures
• - pick up vibrations to send to brain.
2. Semi-circular
Canal – controls
balance.
Smell
• We smell molecules in the air.
Taste
• Taste buds on your tongue sensory receptors for taste.
• six types of touch receptors in your skinhot, cold, pain, pressure, touch, and one for
fine touch.
Touch Mapping Activity
Alcohol and
Your Nervous
System
Alcohol is a depressant.
Depressants – slow the body systems
down.
Reflexes are slowed down, vision is distorted, messages are
sent to the brain by the sensory neurons slower and the motor
neurons respond slower.
BAC – Blood Alcohol Content
http://www.abovetheinfluence.com/facts/drugs-alcohol.aspx?id=search_properAlcohol#
Caffeine and Your
Nervous System
Caffeine is a stimulant.
Stimulant – a drug that
speeds up the nervous
system.
The Amazing Brain
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