spinal cord

Question 1

Cord overview

Answer 1

sensory messages from receptors travel up to brain and messages travel down to the end organ via spinal cord
Located within the vertebral column, surrounded by spinal meninges, Pia mater, dura matter, nachnoid
Bathed in Cerebrospinal fluid between Pia matter and is central canal.

Question 2

protective structures

Answer 2

vertebral column, meninges protect spinal cord and provide physical stability.

Question 3

white matter/ grey matter

Answer 3

myelinated- white matter appears on the outside

unmyellinated- grey matter

Question 4

Coccygeal Plexus

Answer 4

Anterior rami f S4-S5 and cocygeal nerves. supplies small area of skin in coccygeal region

Question 5

Brachial Plexus

Answer 5

Axillary nerve, muscultocotaneous nerve, radial nerve, medial nerve = supplies triceps/biceps
-ant rami of C5-C8 AND T1
Injuries- Wrist drop
Duchene palsy - loss of sensation along lateral arm
roots to trunks to divisions to cords to nerves

Question 6

Plexuses overview

Answer 6

spinal nerves branches are called rami
Plexuses are a group of axons
Anterior rami except T1-11 form plexuses

Question 7

Lumbar plexus

Answer 7

formed by anterior rami of L1-L4

supplies anterolatreal abdominal wall, external genitals, and part of lower limbs

Question 8

Cervical Plexus

Answer 8

anterior rami of C1-C5 phrenic nerves important nerves from cervical plexus

Question 9

Sacral Plexuses

Answer 9

L4-l5 and S1-S4
supplies buttocks, perineum and lower libs
Gives rise to largest NERVE IN BODY- SILATIC NERVE
Injuries- supplies lower limbs
- complete or partial injury leaves deficit in sensation in lower limbs and burning pain etc. eg ankle, hip, toe , knee

Question 10

Sensory spinal cord

Answer 10

Travels along tie major routes in white matter of spinal cord
1- posterior columns, spinothalamic tracts, sensory receptors to dorsal root to thalamus to cortex
2- dorsal root to where cord connects to spinal cord
Receptors are in skin and taken by sensory neutron housed in dorsal root ganglion up to brain via spinal spinal nerve roots to cord and up to brain.

Question 11

Motor spinal cord

Answer 11

motor neurons in anterior ventral horn (grey matter) generates signal , axon tracks to muscle carrying signal. Motor commands leave spinal cord via spinal nerves at anterior ventral root

Question 12

spinal nerves

Answer 12

31 pairs

connective tissue coverings of spinal nerves, epineuriem, perineurium, and endoneurium