Download The Nervous System

Two Subdivisions
1. Central Nervous
System (CNS)


2.
Brain
Spinal cord
Peripheral
Nervous System
(PNS)

Nerves of the body
CNS
 Controls the body
Source of:
 Emotions
 Memory
PNS
 Relays communication
b/w brain and the body

http://www.youtube.com/watch?v=cGSXaWJD75U

http://www.youtube.com/watch?v=_vx1OVLX5Rc
1.
Sensory

2.
Integration

3.
Gathers info
Process Info
Motor


Responds to signals
Maintains homeostasis
1.
Neurons

2.
Process info
Neuroglia
 Support, nourish and
protect

Cell Body
 Contains nucleus

Dendrite
 Receive signals

Axon
 Sends signal along

Synapse
 Site of communication

Schwann Cells (PNS)
 Produce/maintains the
myelin sheath for each
axon

Myelin sheath
 Increases the speed of
nerve impulses
 Increase with age

Why are babies less
coordinated than
adults?

Determined by the #
processes attached to
the cell body
Process

Occurs at a synapse

Neurotransmitters
are released
 Chemical Messengers

The process
 Neurotransmitter
released and binds to
receptor
 Response carried out

http://www.youtube.co
m/watch?v=ifD1YG07f
B8

Resting Potential

Action Potential

What happens when
the action potential
reaches the axon
terminal?

Excitatory



action potentials
release of
neurotransmitter
Inhibitory


action potentials
release of
neurotransmitter
Causes feelings of
euphoria
 Activates the pleasure
center
 Both excitatory
(elevates mood) and
inhibitory (depression)

1.
2.
3.
Was there a difference in the average distances
between arms and fingers for the meter stick
drop? Why do you think this is the case?
How many hours of sleep did you get the night
before our lab? Do you think there is
correlation between reaction time and amount
of sleep? Explain your reasoning.
Was there a difference in average distance
between neurons in the different areas tested
on your body?
a. Which was the shortest and which was the longest?
Why do you think this is the case?

Photoreceptors
 Specialized neurons in
the eye

Optic Nerve
 No photoreceptors
 No info to brain
 Brain “makes up”
missing info