Chapter 13 - Spinal Cord, Spinal Nerves And Spinal Reflexes

Front 1

Spinal Reflex

Back 1

when we pick up something hot, the grasping muscles may relax and drop the object before the sensation of extreme heat or pain reaches our conscious perception. It involves only the spinal nerves and the spinal cord.

Front 2

Spinal Cord

Back 2

- found in the vertebral coloumn

- extends from the brain stem at the foramen magnum of the skull to the first or second lumbar vertebra of the vertebral column

- stops increasing in length by age 4-6, while the vertebral column continues to grow.

Front 3

the amount of ___ _____ in the spinal cord varies along its length. It is greatest in segments dedicated to the ___ and ____ control of the limbs. These segments are expanded and form the emlargements of the spinal cord.

Back 3

Gray Matter, sensory, motor

Front 4

The _____ ______ supplies nerves to the shoulder and upper limbs, where as the ____ _____ supplies nerves to the pelvis and lower limbs.

Back 4

cervical enlargement

lumbar enlargement

Front 5

In sectional view, the gray matter is __ shaped and has two posterior projections, the ___ ___, and two anterior projecitons, the __ __

Back 5

H, posterior, anterior

Front 6

Gray Commissues

Back 6

contain axons that cross from one side of the spinal cord to the other

- section of gray matter near contral canal where axons cross over

Front 7

White Matter vs Gray Matter

Back 7

White: myelinated, 'transmission' of information

Gray Matter: less myelinated, cell bodies, dendrites, 'processing' regions

Front 8

Tracts

Back 8

bundles of neurons in white matter

Front 9

Dorsal Root

Back 9

carry sensory information fro the periphery and viscera up towards the brain.

Front 10

Ventral root

Back 10

carry motor commands down to the spinal cord and out to the effectors,

Front 11

There is a ____ ganglion but not a ___ ganglion.

Back 11

dorsal root, ventral root

Front 12

Spinal nerves begin at the spinal cord as ____.

Back 12

gray matter

Front 13

Know diagram 13.5

Back 13

Know diagram 13.5

Front 14

The _____ ( or _____) enter the dorsal horn and are composed of incoming ____ axons. The cell bodies of sensory neurons are clustered in ____ (singular: __), located just outside the spinal cord.

Back 14

sensory info, posterior root, sensory, ganglia, ganglion

Front 15

The ____ (or ___) exit the anterior horn and are composed of outgoing ___ axons. The cells bodies of ___ ____ are located inside the anterior horn.

Back 15

motor info, anterior root, motor, motor neurons

Front 16

On both sides of the spinal cord, the roots of each nerve pass through the ___ _____ located between successive vertebrae.

Back 16

intervertebral foramina

Front 17

The collection of nerve roots that is not within the spinal cord is called the:

Back 17

cauda equina (horse tail) - part of PNS

Front 18

Spinal Meninges

Back 18

Specialized connective tissue membranes that protect the spinal cord and cauda equina.

Front 19

The ____ ____ are continuous with the ___ ___ that surround the brain.

Back 19

spinal meninges, cranial meninges

Front 20

Three layers of meninges

Back 20

1. Duramater

2. Arachnoid mater

3. Pia Mater

Front 21

Daramater

Back 21

(means tough mother)

- tough, leathery layer. Contains dense collagen fibers oriented along the longitudinal axis of the spinal cord.

Front 22

Arachnoid mater

Back 22

(means spider-like mother) - cobweb-like middle layer

Front 23

Pia Mater

Back 23

(means gentle mother) - delicate covering that follows all of the bumps and indentations in the brain and spinal cord.

- many blood vessels run along the surface of the pia mater, and they supply oxygen and nutrients to the spinal cord.

- ligaments extend from the pia mater through the arachnoid mater to the dura mater to prevent excessive lateral movement of the spinal cord.

Front 24

tract vs nerve

Back 24

collection of neurons:

Tract: CNS (white matter) Nerve: PNS

Front 25

Space between the dura mater and the vertebral wall is called:

Back 25

Epidural space

Front 26

Epidural Block

Back 26

when anesthetics are injected into the epidural to cause a temp. loss of sensory nearby spinal nerves ( and motor nerve paralysis, depending on the anesthetic used). used in child birth.

Front 27

Subarachnoid Space

Back 27

space in between the pia mater and arachnoid mater

Front 28

Cerebral Spinal Fluid

Back 28

found in subarachnoid space and in the central canal of the spinal cord. The CSF cushions the brain and spinal cord from vibrations, and nourishes the cells

Front 29

Spinal Tap (proper name and what?)

Back 29

Lumbar Puncture

CFS is collected. The best place is in the cauda equina where there is more space and fewer nerves than in higher areas of the spinal cord. Helps rule out meningitis.

Front 30

Meningitis

Back 30

an inflammation of the meningeal membranes causes by a bacterial or viral infection. Can also be sterile- no infection, just inflammation (e.g. lupus). It is dangerous because it can disrupt the normal circulation of CSF, leading to damage or death of neurons and neuroglia.

Front 31

Spinal Nerves

Back 31

classified as mixed nerve because they contain both sensory (afferent) and motor (efferent) neurons.

Front 32

31 pairs of spinal nerves... List

Back 32

8 pairs of cervical nerves (C1-C8)
12 pairs of thoracic nerves (T1-T12)

5 pairs of lumbar nerves (L1-L5)

5 pairs of saccral nerves (S1 to S5)

1 pair of coccygeal nerves (Co1)

Front 33

Nerve Plexus

Back 33

A network of nerves

- As most nerves exit the spinal cord they converge to form a network of interwoven nerves (except for the thoracic nerves)

Front 34

Four major plexuses on each side of body:

Back 34

cervical, brachial, lumbar and sacral

Front 35

Ulnar Nerve

Back 35

Funny bone

Front 36

Nerve

Back 36

a cable like bundle of many neuron axons all wrapped together in much the same way that muscle fibers are wrapped together in muscle.

Front 37

Laters of connective tissues in spinal (and cranial) nerves:

Back 37

Epineurium

Perineurium

Endoneurium

Front 38

Epineurium

Back 38

superficial covering over the entire nerve

Front 39

Perimeurium

Back 39

wraps around bundles of axons called fascicles

Front 40

Endoneurium

Back 40

wraps around individual axons

- arteries and veins are found around fascicles, with capillaries that extend into the endoneurium to supply the axons and Schwann cells.

Front 41

A whole structure is called a ___ when it is within the PNS, but if it is within the CNS the same structure is called a ___.

Back 41

nerve, tract

Front 42

Dermatomes

Back 42

where each spinal nerve innervates a specific section on the surface of the skin

- there is some overlap that prevents the complete loss of sensation if one specific nerve is damaged. As a result, sensory anesthesia may require that three spinal nerves be blocked.