module 3 - lecture 9

Question 1

External Anatomy of the Spinal Cord.

Answer 1

• Starts at: Foramen magnum
  = “big hole”, the opening at the base of the skull
• Ends at: inferior border of 1st lumbar vertebra (L1)
  Within a sac, made of meninges, that fits
  inside the spinal cavity
• Spinal cavity within vertebrae

Question 2

regiobs of spinal cord

Answer 2

1. Cervical (7)
2. Thoracic (12 segments)
3. Lumbar (5)
4. Sacral (5)
5. Coccygeal (1)
   Amount of spinal nerves the same
   ONE EXCEPTION! There is an additional pair of spinal nerves in the cervical region.

Question 3

cauda equina

Answer 3

Large collection of long nerves inferior to end of spinal cord - in lumbar.

Question 4

spinal nerves carries infromation in and out of the spinal cord

Answer 4

dorsal nerve roots carry only AFFERENT information
Ventral nerve roots = carry only EFFERENT information

Question 5

peripheral nerve

Answer 5

Axons are covered with endoneurium
Endoneurium-covered axons are bundled
together to form a fascicle
Fascicles are covered with perineurium
Fascicles bundle with each other and with
blood vessels to form a nerve
Nerves are covered by epineurium

Question 6

cranial nerves

Answer 6

nerves of the head. found in the PNS
found in pairs (12)
Take motor information from the brain out to muscles in the head and neck OR
ii. Bring sensory information into the brain from the head and neck OR iii. Some do both]
Travel straight from brain to head and neck.

Question 7

CRANIAL NERVES WE NEED TO KNOW (5)

Answer 7

CN 1 Olfactory - sensory, sense of smell
CN 2 Optic - sensory, sense of sight
CN 5 Trigeminal - Both, * Sensation from face (sensory), Chewing muscles (motor)
CN 7 Facial - Both * Sense of taste (sensory)
Muscles of facial expression (motor)
CN 10 Vagus - Both, * Muscles for breathing (diaphragm), muscles for moving food along the digestive tract, Unconscious sense of blood pressure, heart rate, blood oxygen

Question 8

CN 5 - trigeminal nerve - chewing (motor)

Answer 8

Muscles of mastication
* Move the mandible (lower jaw)
* Multiple muscles – You need to
know two
1. Temporalis
2. Masseter

Question 9

CN 7 - FACIAL

Answer 9

Muscles of facial expression
* Paired muscles
* Frontalis
* Orbicularis oculi
* Orbicularis oris
* Zygomaticus

Question 10

orbicularis

Answer 10

lips - * Controls size and shape of oral opening

Question 11

Orbicularis oculi

Answer 11

Controls size and shape of ocular opening (eyes)

Question 12

Frontalis

Answer 12

(above eyes)
* Controls forehead expression
- Elevates eyes/eyebrows
- Wrinkles forehead

Question 13

Zygomaticus

Answer 13

Elevates angle of mouth (=smile) strands off the lips