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.