The Nervous System
Vocabulary!
1. Neuron
2. Dendrites
3. Axon
4. Synapses
5. Central Nervous
System
6. Peripheral Nervous
System
7. Cerebrum
8. Reflex
The Nervous System
• The Nervous System is a complex network of cells that communicate and
control mental and physical activity within the human body.
• A NEURON is a nerve cell.
• Extending from a nerve cell body are membrane covered extentions
called DENDRITES.
• DENDRITES receive info from other cells and carry info to the cell body.
• Another extension, the AXON, transmits information away from the cell.
• The MYELIN SHEATH insulates the axon and protects it.
• SYNAPSES are juntions between neurons and other cells.
Draw and Label in Your Notes
Structure of the Nervous System
• CENTRAL NERVOUS SYSTEM= the brain and spinal
cord
• The brain is the control center
• The spinal cord carries nerve signals between the
body and the brain
• PERIPHERAL NERVOUS SYSTEM= the neurons that
have cell bodies that are not part of the brain or spinal
cord
The Brain
•CEREBRUM- largest portion of the
human brain, folded outer layer
•2 cerebral hemispheres, 4 lobes (frontal,
parietal, occipital, temporal)
Insert Brain Diagram with labels
• Handout
Brain Pop! Brain
Brain Coloring!
PERIPHERAL NERVOUS SYSTEM
• NERVES are the bundled axons and dendrites found outside the
central nervous system
• The SENSORY DIVISION of the peripheral nervous system contains
sensory receptors and interneurons that connect the outer body
to the central nervous system.
• The MOTOR DIVISION lets the body react to sensory information
• The SOMATIC NERVOUS SYSTEM is a body’s voluntary motor
response (moving your body)
• REFLEXES are involuntary and often self-protective movements
• AUTOMATIC NERVOUS SYSTEM controls internal body conditions
(respiration, heart rate, digestion, etc)
Reflex Activity
• Get a meter stick. Hold the ruler near the end
(highest number) and let it hang down. Have another
person put his or her hand at the bottom of the ruler
and have them ready to grab the ruler (however, they
should not be touching the ruler). Tell the other
person that you will drop the ruler sometime within
the next 5 seconds and that they are supposed to
catch the ruler as fast as they can after it is dropped.
Record the level (inches or centimeters) at which they
catch the ruler.
• Test the same person 3 (vary the time of dropping the
ruler within the 5 second "drop-zone" so the other
person cannot guess when you will drop the ruler).
• Here is a table to convert the distance on the ruler to
reaction time. For example, if you caught the ruler at
the 8 inch mark, then your reaction time is equal to
0.20 seconds (200 ms). Remember that there are
1,000 milliseconds (ms) in 1 second.
Distance
Time
2 in (~5 cm)
0.10 sec (100 ms)
4 in (~10 cm)
0.14 sec (140 ms)
6 in (~15 cm)
0.17 sec (170 ms)
8 in (~20 cm)
0.20 sec (200 ms)
10 in (~25.5 cm)
0.23 sec (230 ms)
12 in (~30.5 cm)
0.25 sec (250 ms)
17 in (~43 cm)
0.30 sec (300 ms)
24 in (~61 cm)
0.35 sec (350 ms)
31 in (~79 cm)
0.40 sec (400 ms)
39 in (~99 cm)
0.45 sec (450 ms)
48 in (~123 cm)
0.50 sec (500 ms)
69 in (~175 cm)
0.60 sec (600 ms)
Reflex Extension
Choose one of the following…test at least 10
persons to answer the question.
•Compare boys vs. girls. On average, are the boys
or girls faster?
• Compare different ages. Who is fastest?...the
older students or younger students?
• Compare the scores after practice. Does
reaction time improve with practice?
Nervous System Clip
SENSORY SYSTEMS
• To survive, organisms must detect changes in the
environment and react appropriately.
• To do this humans use SENSE ORGANS; eyes, ears,
nose, mouth, and skin
• A SENSORY RECEPTOR is a neuron that detects stimuli
(movement, pressure, tension, light, chemicals,
temperature, etc)
SENSORY SYSTEMS Group Presentations
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Your table will be assigned a sensory system.
You must create a small poster of the system
You will give a 2 min presentation of the system
You will then give a 5 question quiz on the system to the class (the quiz can be
done orally or written on the board)
• Quizzes will be graded and turned in for credit!
• Group Topics:
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Vision
Sensory Receptors
Hearing
Balance
Smell and Taste
Touch
Your Choice!
Your Choice!
The Nervous System Crash Course
5 Senses Diagram
•Divide a paper into 5 parts
•In each, describe the sense, include a
minimum of 3 facts about the sense, why it
is important
•Include 1 drawing or diagram for each
•Add color!
Nervous System Coloring