Nervous_System and its explanation each.

Nervous system

1. Nervous System

2. Parts of the Nervous System
•Brain
•Spinal Cord
•Nerves

3. Vocabulary to Know
•Homeostasis
–The regulation of steady, life-maintaining
conditions inside an organism, despite
changes in its environment

4. Nerve Cells
•Neurons
–Basic functioning units of the nervous
system

5. http://ilearn.senecac.on.ca/aahs/health/IHP/ottawa/anatomy/neuron/map/neuron.html

6. http://35.9.122.184/images/40-AnimalStructureAndFunction/

7. Neurons
•Made up of a cell body and branches
called dendritesand axons
–Dendritesreceive messages from other
neurons and send them to the cell body
–Axons carry messages away from the
cell body

8. Any message carried by a neuron is called an impulse Any message carried by a neuron is called an impulse

9. Neurons
A message carried by a neuron is called
an impulse

11. Types of Neurons
•Sensory
•Motor
•Interneuron

12. Sensory Neurons
•Receive information
•Send impulses to the brain or spinal
cord

13. Interneurons
•Send impulses from sensory neurons
to motor neurons

14. Motor Neurons
•Conduct impulses from the brain or
spinal cord to muscles or glands
throughout your body

15. Synapse
•Small space across which an impulse
moves from an axon to the dendrites
or cell body of another neuron

16. Synapse
•An impulse reaches the end of an
axon
•Axon releases a chemical
•Flows across the synapse
•Stimulates the impulse in the dendrite
of the next neuron
•Impulse moves from neuron to neuron

17. http://www.med.harvard.edu/publications/On_The_Brain/Volume7/Number1/images/Neuron.jpg

18. http://mhln.com
An impulse moves in only onedirection across a
synapse -from an axon to the dendrites or cell body of
another neuron.

19. Two Parts of the Nervous System
•Central (CNS)
•Peripheral (PNS)

20. http://inside.salve.edu/walsh/cns_pns.jpg

21. Central Nervous System
•Brain
•Spinal cord

22. The Brain
•Coordinates body activities
•Made up of approximately 100 billion
neurons
•Divided into three major parts-
–the cerebrum
–the cerebellum
–the brain stem.

24. Cerebrum
•The largest part of the brain
•Where thinkingtakes place
•Where memoryis stored
•Where movementsare controlled
•Where impulsesfrom the senses are
interpreted.

26. Cerebellum
•Interpretsstimuli from eyes, ears,
muscles
•Controlsvoluntary muscle movements
•Maintains muscle tone
•Helpsmaintain balance

28. Brain Stem
•Connectsbrain to spinal cord
•Made up of:
_the midbrain, the pons,
Act as pathways connecting various parts
of the brain with each other
_Medulla
controls involuntary actions

29. http://www.cbituk.org/GRAPHICS/brain.gif

30. The Spinal Cord
•Extensionof the brain stem
•Bundlesof neurons that carry
impulses from all parts of the body to
the brain and from the brain to all
parts of your body
extension of the brain stem. It is made up of bundles of neurons that carry impulses from all parts of the body to the brain

31. Researc h
Visit the
Glenc oe
Sc ienc e
W eb site at
tx.sc ienc e.
glenc oe.c o
mfor more
information
about the
nervous
sy stem.
Make a
broc hure
outlining
rec ent
medic al
advanc es.
The
Peripheral
Nervous
Sy stem
Your brain
and spinal
c ord are
c onnec ted
to the rest
of y our
body by
the
peripheral
nervous
sy stem.
The PNS
is made up
of 12 pairs
of nerves
from y our
brain
c alled
c ranial
nerves,
and 31
pairs from
y our spinal
c ord c alled
spinal
nerves.
Spinal
nerves are
made up of
bundles of
sensory
and motor
neurons
bound
together by
c onnec tive
tissue. For
this
reason, a
single
spinal
nerve c an
have
impulses
going to
and from
the brain at
the same
time. Some
nerves
c ontain
only
sensory
neurons,
and some
c ontain
only motor
neurons,
but most
nerves
c ontain
both ty pes
of neurons.
Somatic
and
Autonomic
Sy stems
The
peripheral
nervous
sy stem has
two major
divisions.
The
somatic
sy stem
c ontrols
voluntary
ac tions. It
is made up
of the
c ranial and
spinal
nerves that
go from the
c entral
nervous
sy stem to
y our
skeletal
musc les.
The
autonomic
sy stem
c ontrols
involuntary
ac tions-
those not
under
c onsc ious
c ontrol-
suc h as
y our heart
rate,
breathing,
digestion,
and
glandular
func tions.
These two
divisions,
along with
the c entral
nervous
sy stem,
make up
y our
body 's
nervous
sy stem.

32. Peripheral Nervous System
•Connectsbody to brain & spinal cord
•12 pairsof nerves from your brain
(cranial nerves)
•31 pairsfrom your spinal cord (spinal
nerves)
–Bundles of sensory and motor neurons
held together by connective tissue

33. http://www.christopherreeve.org/Research/Research.cfm?ID=178&c=21

34. Peripheral Nervous System
•Two divisions
–Somatic
–Autonomic

35. http://abdellab.sunderland.ac.uk/lectures/Parmacology/Pics/anatomy/PNS.GIF

36. Somatic Nervous System
•Controls voluntary actions
•Made up of the cranialand spinal
nerves that go from the central
nervous system to your skeletal
muscles

37. Autonomic Nervous System
•Controls involuntary actions-those not
under conscious control-such as your
heart rate, breathing, digestion, and
glandular functions

38. http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/A/autonomic.gif

39. Reflexes
•Involuntary, automatic responseto a
stimulus
•Involves a simple nerve pathway
called a reflex arc