CH 13 Spinal cord

The subdural space

-located between the dura mater and the arachnoid mater.

Which branch carries motor neurons to structures on the back of the body trunk?

1

At what age does the vertebral column continues to elongate, but not the spinal cord?

4

dermatome

A specific strip of skin that is innervated by a specific spinal nerve

Which of the following is true regarding an epidural block?

A) It is commonly used as a method of pain control during labor and delivery. B) It affects only the spinal nerves in the immediate area of the injection. C) It can provide sensory and motor anesthesia, depending on the anesthetic selected. D) It can provide mainly sensory anesthesia, depending on the anesthetic selected. All of the answers are correct

In meningitis,

A) inflammation of the meninges occurs. B) bacteria can be the cause. C) viruses can be the cause. D) CSF flow can be disrupted. All of the answers are correct.

The spinal cord is part of which nervous system?

Central

neuronal pools

Interneuron functional groups

Most complicated spinal reflexes

Intersegmental reflex arcs

perineurium

Layer of connective tissue that surrounds a fascicle within a peripheral nerve

Tina is injured, her knee-jerk reflex is normal and she exhibits a plantar reflex (negative Babinski reflex). These results suggest that Tina has

Suffered NO damage to her spinal cord.

reflex arc.

The neural "wiring" of a single reflex

epineurium

The outermost connective-tissue covering of nerves is the

Suppose that you feel something brushing against your abdomen. The sensory information would be carried to the spinal cord over a(n) ________ ramus.

Ventral

Which statement is *FALSE* regarding reflexes?

You have no conscious control or modification ability over reflex action.

monosynaptic reflex

a sensory neuron synapses *directly* on a motor neuron

Somatic reflexes

activate skeletal muscles

The obturator nerve is distributed to the?

adductors of the hip

Mary is in an automobile accident and suffers a spinal cord injury. She has lost feeling in her lower body. Her doctor tells her that swelling is compressing a portion of her spinal cord. Which part of her cord is likely to be compressed?

ascending tracts

where are muscle spindles NOT found?

in tendons

a crush injury to the C3-C5 spinal segments might cause?

inability to breathe on their own.

Reflexes that activate muscles on the *same side of the body* as stimilus

ipsilateral reflex

The loss of feeling and movement of the JUST *legs* is termed?

paraplegic

The brachial plexus gives rise to all of the following nerves except the

phrenic

tendon reflex

reflex that prevents a muscle from exerting too much tension

Reflexes CANT be classified as

sensory or motor.

In the condition ________, a virus infects dorsal root ganglia, causing a painful rash whose distribution corresponds to that of the affected sensory nerves as seen in their dermatomes

shingles

Identify the structure labeled "6."

sympathetic ganglion

Postganglionic fibers of the autonomic nervous system that innervate internal organs are

sympathetic nerves.

dura mater

tapers inferiorly to form coccygeal ligament.

what made up of nerve tracts or fasciculi?

white columns

The *preganglionic* fibers that connect a spinal nerve with an autonomic ganglion in the thoracic and lumbar region is?

white rami communicantes

what is NOT related to a positive Babinski reflex?

why you close your eyes when you sneeze

Gray horns

-contain *neuron cell bodies. *

The anterior horns

-contain *somatic* motor nuclei -disease in this region will lead to skeletal muscle weakness or paralysis.

white matter

-contains myelinated axons. -has bundles of axons with (common origins, destinations, and functions. )

posterior gray horns

-damage can result in loss of sensation in his torso -contain sensory nuclei -receives information regarding touch and sensation

sciatic

-nerve that approaches the knee, and divides into two branches, the fibular nerve and the tibial nerve

Pia mater

-part of the meninges -direct contact with the spinal cord -contains blood vessels that supply the spinal cord

Ventral root contains

axons of *motor neurons*

dorsal root contains If the dorsal root of is severed?

axons of *sensory neurons* sensory input would be blocked.

crossed extensor reflex

complements the flexor reflex by activating contralateral muscles

subarachnoid space

contains blood vessels traveling within the space to deliver oxygen and nutrients to the spinal cord. -lumbar puncture is given here

dorsal root ganglia

contains cell bodies of sensory neurons.

dorsal ramus

innervates the skin and muscles of the back

ventral ramus

innervates the ventrolateral body surface, structures in the body wall, and the limbs.

neuronal circuit patterns DO NOT include

multipolar

what cannot be modified by the brain?

neural reflexes

divergence

one neuron synapses on several postsynaptic neurons

You are sitting at a Mexican restaurant waiting for your food. The waiter brings a very hot plate, telling you to be careful about touching it. You touch it anyway, producing a pain sensation in your fingers, a withdrawal of your hand, and an auditory comment of what you are thinking. This scenario represents a ________ neuronal circuit.

parallel

The condition in which a person loses all feeling and movement of the *arms and legs* due to spinal cord injury is termed?

quadriplegia

Identify the structure labeled "5."

rami communicantes (white ramus and the gray ramus collectively)

What is the function of the structure labeled "12"?

somatic sensory receiving

where do you inject a anesthetize to a patient?

the epidural space

reciprocal inhibition

when spinal interneurons inhibit antagonist motor neurons

plexus

*Complex, interwoven network of nerves* formed by contributions from the ventral rami of neighboring spinal nerves

polysynaptic reflex

-The delay between stimulus and response is greater -Has at least one interneuron placed between the sensory and motor neurons.

phrenic nerve

-arises in the cervical plexus, innervates the diaphragm -nerve crucial for breathing

innate reflexes

-based on synapses formed during development

Spinal nerves

-both sensory and motor. -has thirty-one segments

Reflexes that activate muscles on the *opposite side of the body* as stimilus

contralateral reflex

What is the function of the structure labeled "14"?

control of visceral effectors

what separates the dura mater from the walls of the vertebral canal?

epidural space

what is a strand of fibrous tissue that provides longitudinal support to the spinal cord as a component of the coccygeal ligament?

filum terminale

conus medullaris

found at L1

The *postganglionic* fibers that connect an autonomic ganglion in the thoracic or lumbar region

gray rami communicantes

Identify the structure labeled "3."

gray ramus

endoneurium

layer of connective tissue that surrounds individual axons within a peripheral nerve

The flexor reflex

moves a limb away from a painful stimulus