chapter 12-13 ap 1

_________________ is a functional division of the PNS includes neural tissues carrying somatic and motor commands out of the CNS to muscles and glands.

Efferent division

Identify the three layers of connective tissue of a spinal nerve

outer epineurium, middle perineurium, and inner endoneurium

In which plexus does the ulnar nerve arise?

brachial

The ventral rami of spinal nerves C4 to T1 contribute fibers to the ________ plexus

brachial

In a ________ neuronal pool, one neuron synapses on several postsynaptic neurons.

diverging

The tough, fibrous, outermost covering of the spinal cord is the

dura mater

______________ target organs that respond to motor commands

effectors

__________________ carries motor commands from CNS to muscles, glands, and adipose tissue

efferent division

The layer of connective tissue that surrounds individual axons within a peripheral nerve is termed the

endoneurium

The outermost connective-tissue covering of nerves is the

epineurium

_____________ are branches of an axon that allow the neuron to communicate with numerous cells

collaterals

In the spinal cord, white matter is separated into ascending and descending tracts organized as

columns

The epidural space contains

connective tissue and blood vessels

The ________ of each spinal nerve innervates the skin and muscles of the back.

posterior ramus

Which ramus provides sensory and motor innervation to the skin and skeletal muscles of the back? (

posterior ramus

Through which root of a spinal nerve does visceral sensory information arrive?

posterior root

List the components of a reflex arc.

receptor, sensory neuron, motor neuron, effector, and sometimes interneurons may be involved

____ Detect changes or respond to stimuli May be neurons or specialized cells May be single cells or complex sensory organs (e.g., eyes, ears)

receptors

Spinal interneurons inhibit antagonist motor neurons in a process called

reciprocal inhibition

In ________, axon collaterals extend back toward the source of the impulse and further stimulate the earlier neurons.

reverberation

If the posterior root of a spinal nerve is severed,

sensory input would be blocked

The posterior horns of the spinal cord contain mainly

sensory nuclei

Compared to the vertebral column, the spinal cord is

shorter

When an anesthetic blocks the function of the anterior rami of the cervical spinal nerves, which areas of the body will be affected?

skin and muscles of the back of the neck and of the shoulders

The anterior horns of the spinal cord contain mainly

somatic motor nuclei

A disease that damages myelin sheaths would affect which portion of the spinal cord?

white matter columns

The preganglionic fibers that carry visceral motor fibers and connect a spinal nerve with an sympathetic ganglion form theA) white rami comm

white rami communicans

The layer of the meninges in direct contact with the spinal cord is the

pia mater

____________________ carries sensory information from receptors in peripheral tissues and organs to CNS

Afferent division

What are common characteristics of reflexes?

All reflexes are rapid, unconscious patterned responses to stimuli that restore or maintain homeostasis.

In which of the following would the delay between stimulus and response be greater? A) a monosynaptic ipsilateral reflex B) a polysynaptic ipsilateral reflex C) a monosynaptic contralateral reflex D) a polysynaptic contralateral reflex

D) a polysynaptic contralateral reflex

Which of the following is not true about a positive Babinski reflex? A) normal in newborns B) abnormal in adults C) a sign of injury to descending spinal tracts D) causes you to close your eyes when you sneeze E) causes flaring of the toes when the sole is stroked

D) causes you to close your eyes when you sneeze

Reflexes, controlled by the spinal cord, act by A) sensory output over cranial nerves to effectors .B) motor input to reflex centers in the spinal cord. C) sensory input to reflex centers in the brain. D) motor output over spinal nerves to effectors. E) sensory input over cranial nerves to the spinal cord.

D) motor output over spinal nerves to effectors.

All of the following are true of neural reflexes except that they A) are automatic motor responses. B) are the simplest form of behavior. C) help preserve homeostasis. D) usually cannot be suppressed by the brain. E) involve at least two neurons.

D) usually cannot be suppressed by the brain.

All of the following terms refer to ways that reflexes can be classified except A) intersegmental. B) polysynaptic. C) innate. D) voluntary. E) somatic.

D) voluntary.

Blood vessels traveling within ________ deliver oxygen and nutrients to the spinal cord. A) the pia mater B) the arachnoid mater C) the dura mater D) all three cranial meninges E) all three spinal meninges

E) all three spinal meninges

Reflexes can be classified according to all of the following except A) where they are initiated .B) where information processing occurs. C) the motor response. D) the complexity of the neural circuit. E) whether they are sensory or motor.

E) whether they are sensory or motor.

What is the significance of the cauda equina?

It is made up of extensions of the posterior and anterior roots of spinal segments L2 to S5. It forms as the vertebral column continues to elongate after growth of the spinal cord ceases at about age 4.

The face, head, and cheeks are located in a dermatome supplied by nerves from what spinal cord region?

No spinal nerves innervate the dermatome containing the face.

___________________________ Includes all nervous tissue outside CNS and ENS Delivers sensory information to the CNS Carries motor commands to peripheral tissues

Peripheral nervous system (PNS)

Differentiate between sensory nuclei and motor nuclei.

Sensory nuclei receive and relay sensory information from peripheral receptors; motor nuclei issue motor commands to peripheral receptors.

In the patellar reflex, how does stimulation of the muscle spindle by gamma motor neurons affect sensitivity and reaction time?

The muscle spindles become more sensitive and the reflex response occurs more quickly.

The flexor reflex moves...

a limb away from a painful stimulus

Define stretch reflex

a monosynaptic reflex that provides regulation of skeletal muscle length.

The obturator nerve is distributed to the

adductors of the hip

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

anterior

Sensory nuclei receive and relay sensory information from peripheral receptors; motor nuclei issue motor commands to peripheral receptors.

anterior gray ramus

Sensory input from interoceptors of the body walls and limbs is carried to the spinal nerve via the

anterior rami

The ________ innervate(s) the ventrolateral body surface, structures in the body wall, and the limbs.

anterior ramus

Which ramus carries sensory information from the limbs?

anterior ramus

Nerve tracts or fasciculi make up the

anterior white columns

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 in the lumbar region of her spinal cord.

The anterior root of a spinal nerve contains

axons of motor neurons

All of the following are a part of a monosynaptic reflex arc except A) effector. B) interneuron. C) CNS processing .D) motor neuron. E) sensory neuron.

b) interneuron

Each peripheral nerve provides ________ innervation to peripheral structures.

both motor and sensory

The white matter of the spinal cord contains

bundles of axons with common origins, destinations, and functions.

Describe the composition of the gray matter of the spinal cord. (Module 12.2D)

cell bodies of neurons, neuroglia, and unmyelinated axons

posterior root ganglion contains ___

cell bodies of sensory neurons

The posterior root ganglia mainly contain

cell bodies of sensory neurons.

The ________ plexus supplies innervation to the diaphragm.

cervical

Which kind of neural circuit processes information in a stepwise fashion, one neuron to another?

convergent

The ________ reflex complements the flexor reflex by activating contralateral muscles.

crossed extensor

_____________ are slender processes that extend from the cell body and are the structures used to transmit information into the cell body

dendrites

The ________ is a strand of fibrous tissue that provides longitudinal support as a component of the coccygeal ligament.

filum terminale

Axons crossing from one side of the spinal cord to the other within the gray

gray commissures

The postganglionic fibers that connect an sympathetic ganglion and carry fibers that innervate glands and smooth muscle of the body wall or limbs are the

gray rami communicans

Enlargements of the spinal cord occur

in those spinal segments that control the limbs.

The stretch reflex

is important in regulating muscle length.

In an adult, the conus medullaris is found at about

l1

A viral disease that destroys the neuronal cell bodies of the anterior gray horn will

lead to muscle weakness or paralysis.

Spinal nerves from the sacral region of the cord innervate the ________ muscles.

leg

Bill contracts a viral disease that destroys cells in the posterior gray horns in his spinal cord. As a result, which of the following would you expect?

loss of sensation

Somatic motor neurons in the spinal cord control all of the following muscles except those that

move the face

The white matter of the spinal cord is mainly

myelinated axons.

________________ or glial cells are essential to survival and function of neurons and preserve structure of nervous tissue

neuroglia

The gray horns of the spinal cord contain mainly

neuron cell bodies

_______________ is the cytoplasm around the nucleus containing neurofilaments and neurotubulesright answer feedback:

perikaryon

Blood vessels that supply the spinal cord are protected by the

spinal meninges

A posterior and anterior root of each spinal segment unite to form a

spinal nerve

The myotatic reflex is also known as the ________ reflex.

stretch

Cerebrospinal fluid flows within the

subarachnoid space

During the procedure known as a spinal tap, a needle is inserted into the ________ in the inferior ________ region.

subarachnoid space; lumbar

__________ are the end of axons and telodendria that often contain neurotransmitters used to communicate to other cells at a synapse

synaptic terminal

muscle spindles are NOT found in ____

tendons

Describe a dermatome

the bilateral sensory region monitored by a single pair of spinal nerves.