unit3 - spinal cord & spinal nerves

Define somatic nerve fibers.

Nerve fibers that innervate skin, skeletal muscles, bones, and joints

In Amyotropic Lateral Sclerosis excess glutamate leads to motor neuron destruction with subsequent scarring (sclerosis) of the _____ regions of the spinal cord.

lateral

Neurons of the sympathetic nervous system are found in _____ horns of the spinal cord

lateral

The branch of the spinal nerve that innervates the meninges as well as the vertebrae and spinal ligaments is the _____ branch.

meningeal

A series of fibrous connective tissue membranes covering the central nervous system is referred to as the _____.

meninges

A nerve containing both sensory and motor nerve fibers is called a _____ nerve.

mixed

Based on the presence of both efferent and afferent fibers, spinal nerves are classified as which of the following?

mixed

The simplest reflex arc is ______.

monosynaptic

The anterior horns of the spinal cord contain somas of somatic _____ neurons.

motor

The anterior root of a spinal nerve contain axons of which neurons?

motor

he anterior root of a spinal nerve contain axons of which neurons?

motor

Poliomyelitis is caused by a virus that destroys ______.

motor neurons in the brainstem and anterior horn of the spinal cord

Efferent fibers carry _______ signals ______ the CNS

motor, from

A cordlike organ within the peripheral nervous system composed of numerous nerve fibers (fascicles) bound together by connective tissue is referred to as a _____.

nerve

A nerve is comprised of _____.

numerous fascicles bound together by connective tissue

The connective tissue layer surrounding a nerve fascicle is called the _____.

perineurium

Inferior to the medullary cone, the terminal filum is formed by the _____ mater.

pia

Innervation to the local muscles, joints, and skin of the back is provided by the ______ ramus of a spinal nerve.

posterior

The spinal nerve roots carrying afferent (sensory) nerve signal are the _____ roots.

posterior

The distal branches of a spinal nerve include which of the following?

posterior and anterior rami

Which spinal cord areas are composed of gray matter? Select all that apply.

posterior horn, lateral horn, anterior horn

Moving peripherally from the spinal cord, the anterior and posterior _____ form the spinal nerve

root/roots

Moving peripherally out from the spinal cord, spinal nerve _____ are the closest structures to the spinal cord.

rootlets

What structure of the spinal nerve is situated closest to the spinal cord?

rootlets

Nerve plexuses arise from spinal nerves in which regions? Select all that apply.

sacral, cervical, lumbar

Cell bodies found within posterior root ganglia are those of _______ neurons.

sensory

Afferent nerve fibers carry ______ signals ______ the CNS.

sensory, to

Posterior roots which enter the posterior horn of the spinal cord convey _____ fibers.

sensory/afferent

Nerve fibers that innervate skin, skeletal muscles, bones, and joints are classified as _____.

somatic

Nerve fibers that innervate more localized organs in the head (eyes, ears, olfactory and taste receptors, etc.) are classified as _____ fibers.

special

The cerebrospinal fluid circulates in the _____ space between the meninges.

subarachnoid

In which does cerebrospinal fluid circulate?

subarachnoid space

The lateral horns of the spinal cord contain neurons of the ______ nervous system.

sympathetic

Monosynaptic reflex arcs are rapid because ______.

there is only one synapse for delay

Nerve fibers that innervate blood vessels, glands, and internal organs are classified as _____.

visceral

An abundance of myelinated axons arranged in tracts located superficial to the gray matter of the spinal cord makes up the _____ matter

white

An abundance of myelinated axons arranged in tracts makes up the _______ matter of the spinal cord.

white

A cluster of neuron cell bodies outside of the CNS, i.e. in the periphery is referred to as a _____.

ganglion

Nerve fibers that innervate widespread organs such as muscles, skin, glands, viscera, and blood vessels are classified as _____ fibers.

general

Neuron cell bodies, dendrites, and synapses are found in the CNS within the _____ matter.

gray

All spinal nerves except C1 pass through which structure to emerge from the vertebral column?

intervertebral foramen

In Amyotrophic Lateral Sclerosis, motor neurons are destroyed with subsequent scarring (sclerosis) of the ______ regions of the spinal cord.

lateral

Into what cavity is an epidural anesthetic delivered?

The space between the vertebral bones and dural sheath

What are the regions of the spinal cord?

Thoracic, lumbar, cervical, sacral

A motor nerve is defined as ______.

a nerve containing only fibers carrying outgoing nerve signals from the CNS

Nerve fibers carrying signals toward the central nervous system from receptors are classified as _____.

afferent

Innervation to the anterior and lateral skin and muscles of the trunk and limbs is provided by the ______ ramus of of a spinal nerve.

anterior

The intercostal nerves arise from the ______ rami of the ______ spinal nerves.

anterior, thoracic

The neural pathway that mediates a reflex is called a reflex _____.

arc

Somatosensory nerves carry signals from ______.

bones, muscle and skin

Gray matter is found in the _____.

brain and spinal cord

White matter is found in the ______.

brain and spinal cord

The bundle of nerve roots occupying the vertebral canal from L2 to S5 is referred to as the _____ _____.

cauda equina

The central canal contains ______.

cerebrospinal fluid

A sensory nerve is defined as ______.

containing only fibers carrying incoming nerve signals to the CNS

The epineurium is composed of ______.

dense irregular connective tissue

An area of skin supplied by a single spinal nerve is referred to as a ______.

dermatome

Nerve fibers carrying nerve signals from the CNS to effectors are classified as _____.

efferent

Anterior roots of the spinal cord contain axons of ______ neurons.

efferent, motor, somatic

External to the neurilemma of a nerve fiber is the layer of loose connective tissue that surrounds a nerve fiber called the

endoneurium

Pain during childbirth is often managed by injecting an anesthetic into which space?

epidural space

Identify the connective tissue layer that surrounds the entire nerve.

epineurium

The nerve fiber covering made of dense irregular connective tissue which protects the nerve from stretching and injury is the ______.

epineurium

True or false: Reflexes are spontaneous actions.

false

Within a nerve, nerve fibers are gathered into bundles called _____.

fassicles

The poliomyelitis virus is spread through ______.

fecal contamination of water

Which are considered a distal branch of a spinal nerve? Choose all that apply.

-Posterior ramus -Anterior ramus

A mixed nerve is defined as ______. Select all that apply.

-a nerve that conducts signals in two directions. -a nerve containing both sensory and motor nerve fibers -a nerve containing both afferent and efferent nerve fibers.

Identify characteristics of a reflex. Select all that apply.

-involuntary -responses to sensory input -quick

Somatosensory signals are sent in response to changes in which of the following stimuli? Select all that apply.

-pain and pressue -touch, heat, stretch

Place the meninges in order from superficial to deep.

1. Dura mater 2. Arachnoid mater 3. Pia meter

Adult humans have ______ pairs of spinal nerves arising from the spinal cord.

31

What is the cauda equina?

A bundle of nerve roots occupying the vertebral canal from L2 to S5

Which are made of gray matter?

Anterior, posterior and lateral horns

Functions of the spinal cord include which of the following?

Conduction, locomotion, reflexes

What are meninges?

Fibrous connective tissue membranes covering the central nervous system

The first cervical spinal nerve emerges between which two structures?

Skull and vertebra C1

The anterior horns of the spinal cord contain the somas of which neurons?

Somatic motor