Transcript Nervous System - SteinkeScience

Nervous System
March 31, 2008
Take me to your leader….

The Human Brain

Functions
Control center for movement, sleep, hunger, thirst,
and all activities necessary for survival.
 Human emotions: love, hate, fear, anger, elation,
and sadness are controlled by the brain.
 This makes us conscious, emotional, and
intelligent


The human brain weighs about 3 pounds, which is
made of 100 billion nerve cells. It is encased in three
protective membranes called meninges:




Dura mater
Arachnoid Layer
Pia Mater
The brain and spinal cord are bathed in a fluid that
protects the internal part of the brain (cushion) and is
a medium for the transportation of chemicals within
the nervous system.
CNS
PNS
Nervous Tissue
Neuroglia
Neurons
Structure of Nerve Cells--Insulation
Myelin
Schwann cells Myelin Sheath
Structure of Nerve Cells
Ganglia
White Matter
Gray Matter
Nerve Impulses
Polarized
Depolariz
ed
Repolarized
Inactive
Active
Restore Balance
Potassium Ions (+) inside cell,
Sodium Ions (+) outside cell.
Overall inside cell less + ions than
inside cell.
Sodium
Sodium cannot diffuse,
Ions rush but potassium does—1st
into cell,
restoring the negative
making it
internal environment
more
and positive external
positive
environment, then
than
Sodium Potassium
outside
Pump restores balance
the cell.
between the
Action
potassium/sodium.
potential
(IMPULS
E)
Reflex Arcs
Autonomic
Somatic
Digestion, Elimination, Blood
Pressure, Sweating
Skeletal Muscles
(1) Receptor (2) Effectors organ (3) Afferent Neurons (4) Efferent
Neurons
Many Reflexes only involve spinal cord neurons
Brain Structure and Function
Cerebrum
Limbic
Frontal Lobe
Reasoning,
Planning,
Parts of
speech,
Movement,
Emotions,
and Problem
solving
Thalamus
Motor Control
Receives
Auditory,
Somatosensory
and Visual
Sensory Signals
Parietal Lobe
Movement,
Orientation,
Recognition,
Perception of
stimuli
Hypothalamus
Controls
Autonomic,
Emotions
Homeostasis
Motor Functions
Regulates Food
and Water Intake
Regulates Sleep
Wake Cycle
Occipital
Lobe
Visual
processing
Amygdala
Memory, emotion,
and fear
Temporal
Lobe
Perception
and
recognition
of auditory
stimuli,
memory, and
speech
Hippocampus
Learning and
memory
converting short
term memory to
permanent
memory
Cerebellum
“Little
Brain”
Regulation
and
coordination
of movement,
posture, and
balance
Brain Stem
Mid-Brain
Vision,
hearing, eye
movementand
voluntary
motor
function.
Pons
consciousness
and for sleep.
Medulla
Maintains
vital body
functions,
such as
breathing and
heart rate