Transcript File

WARM UP 3/17
1. What is a Schwann cell?
2. What are interneurons?
3. What are the 2 divisions of the
autonomic?
4. What are the 3 meninges in order?
5. What is the sympathetic system?
6. Name 3 things that the sympathetic does?
NOTES CH 10: 3/17
SPINAL CORD
FUNCTION
1. Brings messages to and from the brain
2. Reflex center
STRUCTURE
• Approx. 17” long
• From brain base
to 1st lumbar
vertebrae
• Size of thumb
• Center looks like an “H”
- gray matter – cell bodies
- white matter – myelinated axon
(more white mater on top – all axons from
body go through there)
TRACTS = bundles of nerves
1. ASCENDING TRACTS – carry impulses
up the sp cord (afferent neurons)
2. DESCENDING TRACTS – carry impulses
down the sp cord (efferent neurons)
A pair of SPINAL NERVES exit
from each segment of the sp cord
31 pairs total:
8 prs – cervical nerves
12 prs – thoracic
5 prs – lumbar
5 prs – sacral
1 coccygeal
EXTRA CREDIT OPP.
There are 31 pairs of spinal nerves……
If you can memorize all 31 in 2 minutes, then you
get an ec slip….BUT
If you don’t get them all, then you have to lose 5
participation points from your grade.
WHO WANTS TO PLAY?????????????
SPINAL CORD NERVE
NAMES
C1, C2, C3, C4, C5, C6, C7, C8
T1, T2, T3….. T12
1L, 2L …5L
1S, 2S …. 5 S
coccygeal
PARALYSIS – if sp cord cut or crushed, loss
of senses and motor of area below it
PARAPLEGIC – legs paralyzed
QUADRAPLEGIC – arms and legs paralyzed
LABELING
1. Dura mater
2. Subdural space
3. Arachnoid
4. Pia mater
5. Skin
6. Periosteum
7. Bone
Dura mater
9. Arachnoid
10. Pia mater
8.
11. Spinal cord
12. Dorsal root
13. Ventral root
** Central canal
14. Dura mater
15. Arachnoid
16. Pia mater
17. Spinal nerves
18. vertebrae (bone)
On labeling sheet
HOW A MESSAGE TRAVELS
THROUGH THE BODY
1. Stimulus detected by receptors
2. Impulse travels through afferent neurons
to spinal cord (* see steps through a
neuron)
3. Ascending tract up spinal cord to brain
4. Brain interprets message
5. MESSAGE CAN STOP HERE OR
CAUSE A REACTION
6. Brain sends response
7. Descending tract down spinal cord from
the brain
8. Impulse travels through efferent neurons
to muscle or gland
9. Body response