anatomy 1 ch 13

In response to a muscle being stretched, a muscle spindle initiates a somatic spinal reflex that causes 1. contraction of the effector muscle. 2. relaxation of the antagonist muscle. 3. contraction of the antagonist muscle. 4. relaxation of the effector muscle. a) 1 only b) 2 only c) 3 only d) 4 only e) 1 and 2 f) 1 and 3 g) 2 and 4

1 and 2

Name and describe the locations of the four major plexuses of spinal nerves

1. Cervical: alongside C1 through C4; 2. Brachial: inferior and lateral to C4 through T1 and superior to rib, posterior to clavicle; 3. Lumbar: lateral to L1 through L4 passing obliquely posterior to psoas major and anterior to quadratus lumborum; 4. Sacral: L4-S3; anterior to sacrum.

Identify and describe the function of each of the components of a spinal reflex arc

1. Receptor: responds to specific changes in body conditions by producing graded potential; 2. Sensory neuron: conducts impulse from receptor to integrating center in gray matter of spinal cord; 3. Integrating center: site of synapse between sensory and other neurons; decision-making area in gray matter of spinal cord; 4. Motor neuron: conducts impulse from integrating center to effector; 5. Effector: is the structure that promotes change in body conditions by responding to motor nerve impulse, such as a muscle or a gland

A typical spinal nerve has how many connections to the spinal cord? a) 1 b) 2 c) 3 d) 4 e) 5

2

In response to a tendon being stretched excessively, a tendon organ initiates a somatic spinal reflex that causes 1. contraction of the effector muscle. 2. relaxation of the antagonist muscle. 3. contraction of the antagonist muscle. 4. relaxation of the effector muscle. a) 1 only b) 2 only c) 3 only d) 4 only e) 3 and 4 f) 1 and 2

3 and 4

Describe the basic anatomy of a spinal nerve plexus

: Axons from the anterior rami of spinal nerves do not go directly to the body structures they supply. Instead, they form networks called plexuses on both the left and right sides of the body by joining with various numbers of axons from anterior rami of adjacent spinal nerves. Thus, the nerves that emerge from a plexus and innervate body organs contain nerve fibers from multiple spinal nerves

Discuss the clinical significance of dermatomes

: Knowing which spinal cord segments supply each dermatome makes it possible to locate damaged regions of the spinal cord. If the skin in a particular region is stimulated but the sensation is not perceived, the nerves supplying that dermatome are probably damaged.

In a stretch reflex, [dropdown 1] detect the muscle stretch. A somatic sensory neuron sends signals to [dropdown 2] in the anterior gray horn and to inhibitory [dropdown 3] in the integrating center. This stretch reflex primary motor path would be classified as [dropdown 4]. This primary pathway [dropdown 5] the effector muscle and [dropdown 6] the antagonist muscle. Dropdown 1 choices: muscle spindles tendon organs nociceptors Dropdown 2&3 choices: interneuron motor neuron Dropdown 4 choices: ipsilateral contralateral Dropdown 5 choices: and f Inhibits Excites

Answer 1: muscle spindles Answer 2: motor neuron Answer 3: interneuron Answer 4:ipsilateral Answer 5: excites Answer 6: inhibits

Denticulate ligaments are thickenings of [dropdown 1] that extend and fuse with the [dropdown 2] and inner surface of the [dropdown 3] Dropdown choices: arachnoid mater dura mater pia mater

Answer 1: pia mater Answer 2: arachnoid mater Answer 3: dura mater

The crossed-extensor reflex integrating center is [dropdown 1] since several sensory neurons synapse with interneurons that synapse with motor neurons. The interneurons excite motor neurons in several segments which is known as a [dropdown 2] reflex. This is a [dropdown 3] since the motor information exits the opposite side of the body from the sensory input. At the neuromuscular junction, [dropdown 4] is released to [dropdown 5] the muscle that will extend. Dropdown 1 choices: polysynaptic monosynaptic Dropdown 2 choices: reciprocal innervation intersegmental reflex arc Dropdown 3 choices: contralateral reflex arc ipsilateral reflex arc Dropdown 4 choices: acetylcholine norepinephrine Dropdown 5 choices: inhibit excite

Answer 1: polysynaptic Answer 2: intersegmental reflex arc Answer 3: contralateral reflex arc Answer 4: acetylcholine Answer : excite

The cell bodies of the neurons that carry information from the periphery to the spinal cord are structurally classified as [dropdown 1] and functionally classified as [dropdown 2] and their cell bodies are located in [dropdown 3]. Dropdown 1 & 2 choices: Sensory Motor Integrative Dropdown 3choices: anterior gray horn anterior root dorsal root ganglion lateral gray horn posterior gray horn

Answer 1: sensory Answer 2: sensory Answer 3: dorsal root ganglion

Inability to abduct or adduct fingers or loss of sensation in the pinky finger would occur from damage to the [___]. Dropdown choices: brachial plexus cervical plexus coccygeal plexus lumbar plexus sacral plexus

brachial plexus

Describe the gross external anatomy of the spinal cord

The spinal cord is roughly cylindrical, but slightly flattened anterior/posterior. It extends from the medulla to the superior border of L2. The length ranges from 42-45 cm and is approximately 2 cm in diameter. There is a cervical enlargement from C4-T1 and a lumbar enlargement from T9-T12. The conus medullaris is the tapered inferior end. The filum terminale is an extension of the pia mater that anchors the cord to the coccyx. The cauda equina is the roots of spinal nerves angling inferiorly in the vertebral canal from the end of the spinal cord. 31 pairs of spinal nerves leave the cord at regular intervals through the intervertebral foramina.

Describe the cross-sectional anatomy of the spinal cord

The spinal cord is slightly flattened in its anterior-posterior dimension. It has two grooves: anterior median fissure and shallower posterior median sulcus. The central canal contains CSF. The gray commissure surrounds the central canal, and forms the cross bar of the H. It contains the axons that connect the two sides of the gray horns (anterior, posterior, lateral). White matter surrounds the gray and is subdivided into columns (anterior, posterior, lateral). The anterior white commissure is anterior to the gray commissure.

Which are functions of the spinal reflexes that use muscle spindles and tendon organs as sensors? Select all that apply. a) Awareness of muscle tension in body b) Prevention of damage to muscles c) Awareness of muscle length d) Prevention of damage to tendons e) Maintenance of muscle tone f) Maintenance of balance g) Avoidance of moving away from a painful stimulus

a b c d e

Which statements describe dermatomes? Select all that apply. a) Can be used clinically to determine area of spinal cord damage b) Complete anesthesia of a single dermatome often requires blocking three adjacent spinal nerves c) Indicate which muscles are innervated by each spinal d) The dermatome serving the face is supplied by the trigeminal cranial nerve e) Are used to check for motor function f) nerve Dermatomes are designated based on the cranial or spinal nerve that serves that area of the skin

a b d f

) Intercostal nerves can be described by what statements below? Select all that apply a) are also known as thoracic nerves b) do not enter into a plexus c) extend through the sacrum d) are formed from the posterior rami e) directly connect to the structures they supply f) are important in controlling the diaphragm

a b e

Which statements describe the spinothalamic tract? Select all that apply a) Begins in the spinal cord b) Terminates in the thalamus c) Found in the gray matter of the spinal cord d) Carries motor information down the cord e) Carries information for pain, temperature and tickle

a b e

The area of the skin that provides sensory input to the CNS via one pair of spinal nerves is called a) a dermatome. b) a microtome. c) perineurium. d) a fascicle. e) an epitome.

a dermatome

When the quadriceps muscle extends the lower leg in the patella reflex, what is occurring in the motor neuron to produce an action potential? a) Influx of sodium and efflux of potassium b) Influx of sodium and efflux of calcium c) Influx of potassium and efflux of sodium d) Influx of both sodium and potassium e) Efflux of both sodium and potassium

a) Influx of sodium and efflux of potassium

Which of the following lists the connective tissue coverings of the axons, fascicles, and entire nerve in the correct order? a) endoneurium, perineurium, epineurium b) endoneurium, epineurium, perineurium c) perineurium, epineurium, endoneurium d) epineurium, endoneurium, perineurium

a) endoneurium, perineurium, epineurium

Sensory information travels to the brain via a) Ascending tracts b) Descending tracts c) Integration tracts d) Anterior roots e) Direct motor pathways

ascending tracts

Which nerve innervates the muscle that abducts the arm at the shoulder and the skin overlying the deltoid? a) phrenic nerve b) axillary nerve c) intercostal nerve d) ulnar nerve e) common fibular nerve

axillary nerve

The ___nerve would be involved with a dancer performing pointe (standing on their toes). Select all that apply a) femoral nerve b) obturator nerve c) tibial nerve d) common fibular nerve e) intercostal nerve

b c

Spinal nerves 1. Are part of the PNS. 2. connect the CNS to sensory receptors and effectors in all parts of the body. 3. are named according to the region of the vertebral column from which they emerge. 4. are mixed nerves. 5. only transmit sensory information. 6. only transmit motor information. a) 1, 2, 3 b) 1, 2, 3, 4 c) 1, 3, 6 d) 1 and 3 e) 1, 2, 3, 4

b) 1 2 3 4

A patient is being examined for muscle weakness. To assess their condition, the doctor tests their knee-jerk reflex by tapping the patella tendon with a reflex hammer and tapping his lower jaw with your finger. Both pathways are considered monosynaptic. What do they have in common? a) They are both autonomic, cranial reflexes b) They both a two neuron pathway, sensory to motor c) They are both somatic, autonomic reflexes d) The sensory neurons exit the same segment of the spinal cord

b) They both a two neuron pathway, sensory to motor

The spinal cord ends a) between L1 and L2 b) at T12 c) at S5 d) at L5 e) between T9 and T10

between L1 and L2

What parts of a neuron within a nerve is/are wrapped in a protective endoneurium? 1. Myelinated axon 2. Unmyelinated axon 3. Dendrites a) 1 only b) 2 only c) 3 only d) Both 1 and 2 e) 1, 2 and 3

both 1 and 2

A patient who has loss of pin prick sensation starting at the level of the nipple and downward on the right side would have a lesion in the spinal cord at which level? a) C7-C8 b) T4-T5 c) T6-T7 d) T10-T12 e) S1-S2

c) T6-T7

Why is a spinal tap performed below L2 of the spinal cord? a) The spinal cord is present ensuring there will be a subarachnoid space present. b) The spinal meninges and spinal cord are not present, ensuring no damage to the nervous system. c) The spinal meninges and spaces extend passed the proper spinal cord, allowing fluid to be withdrawn with a minimal risk of damage to the spinal cord. d) There is more space between the vertebrae in a flexed position below L2. e) The supracristal line is the only way to determine placement of the needle in spinal taps

c) The spinal meninges and spaces extend passed the proper spinal cord, allowing fluid to be withdrawn with a minimal risk of damage to the spinal cord.

Which of the following spinal nerves does not travel through an intervertebral foramen to reach its destination? a) cervical spinal nerve 1 b) thoracic spinal nerve 12 c) lumbar spinal nerve 2 d) sacral spinal nerve 1 e) cervical spinal nerve 7

cervical spinal nerve 1

Which type of descending motor pathway conveys nerve impulses that originate in the cerebral cortex and allows you to use your fingers for sewing and sign language? a) vestibulospinal tract b) corticospinal tract c) reticulospinal tract d) spinothalamic tract e) gracile fasciculus

corticospinal tract

A pupillary reflex is integrated in the brain stem so it is classified as a ________reflex. The smooth muscle of the iris is the effector, so this is classified as a(n) ___________. a) Spinal; somatic b) Spinal; autonomic c) Cranial; somatic d) Cranial; autonomic e) Spinal; visceral

cranial: autonomic

Place the reflex arc components in order from detecting a stimulus to response. 1. motor neuron 2. effector 3. sensory neuron 4. integration center 5. sensory receptor a) 5, 1, 2, 4, 3 b) 3, 5, 1, 2, 4 c) 3, 5, 4, 1, 2 d) 5, 3, 4, 1, 2 e) 2, 1, 4, 3, 5

d) 5 3 4 1 2

In reciprocal innervation of the tendon reflex stimulation of afferent fibers causes a) inhibition of effector muscles b) inhibition of antagonist muscles c) excitation of effector muscles d) excitation of antagonist muscles e) excitation of muscles on the contralateral side

d) excitation of antagonist muscles

Which spinal meninges is composed of collagen fibers arranged in an irregular pattern that is very strong? a) Arachnoid mater b) Dura mater c) epineurium d) Pia mater

dura matter

Which of the following parts of a reflex arc would be represented by the contraction of the gastrocnemius muscle or the radial iris muscles? a) Sensory receptor b) Sensory neuron c) Motor neuron d) Effector e) Integrating center

effector

Which layer of protective connective tissue covers a nerve and fuses with the outer menix layer? a) dura mater b) pia mater c) endoneurium d) perineurium e) epineurium

epinerium

The largest nerve in the lumbar plexus is the [___]. common fibular femoral nerve obturator nerve sciatic nerve tibial nerve

femoral nerve

Which of the following parts of a reflex arc can be monosynaptic or polysynaptic? a) Sensory receptor b) Sensory neuron c) Motor neuron d) Effector e) Integrating center

integrating center

The nerves that supply the thigh and calf of leg emerge from the a) lumbar enlargement b) filum terminale c) cauda equina d) conus medullaris e) cervical enlargement

lumbar enlargement

In the 400 meter relay, runners handoff the baton to the person in front of them. The second runner in the relay team had to be replaced . They were unable to pronate their forearm to reach behind for the baton because of injury to their brachial plexus. What is the most likely site of their injury? a) Dorsal scapular nerve b) Intercostal nerve c) Phrenic nerve d) Median nerve e) Radial nerve

median nerve

An individual suffers a stroke and looses control over their left arm. The individual is affected with__________paralysis. a) diplegia b) monoplegia c) paraplegia d) hemiplegia e) quadriplegia

monoplegia

Which branch of a spinal nerve serves the deep muscles and skin of the posterior surface of the trunk? a) Meningeal branch b) Rami communicantes c) Intercostal nerve d) Posterior ramus e) Anterior ramus

posterior ramus

A nerve impulse initiated at a muscle spindle has to travel through which of the following structures to enter the integrating center? a) Anterior root of spinal nerve b) Posterior root of spinal nerve c) Tectospinal tract d) Gray commissure e) Lateral reticulospinal tract

posterior root of spinal nerve

If these structures were severed, the nerve impulses from pain and stretch receptors would not reach the CNS. a) white columns b) gray horns c) anterior root of spinal nerves d) posterior root of spinal nerves e) rami communicantes

posterior root of spinal nerves

Which region of the spinal cord allows a dancer to be aware of their movements and body position? a) Posterior white column b) Anterior gray horn c) Anterior white column d) Lateral white column e) Gray commissure

posterior white column

In an episiotomy, a surgical cut at the opening of the vagina, during childbirth, anesthetization to the [___] nerve may occur. Answer options femoral obturator perforating cutaneous pudendal sciatic

pudendal

Excitation of the quadriceps femoris group and inhibition of the hamstring group is termed _______ innervation. a) antagonist-effector b) ipsilateral c) crossed-extensor d) reciprocal e) Intersegmental

reciprocal

When an individual sits for a period of time, their leg may 'fall asleep'. This sensation is usually a result of [___] nerve compression. Dropdown choices: ilionguinal femoral medial obturator sciatic

sciatic

Which of the following parts of a reflex arc would involve the posterior root ganglion? a) Integrating center b) Sensory neuron c) Motor neuron d) Effector e) Interneuron

sensory neuron

Which of the following parts of a reflex arc monitors the rectus femoris muscle stretching? a) Sensory receptor b) Integrating center c) Motor neuron d) Effector e) Interneuron

sensory receptor

Which structure listed contains cerebrospinal fluid? a) epidural space b) subarachnoid space c) subdural space d) foramen magnum e) posterior median sulcus

subarachnoid space

A severed obturator nerve will lead into paralysis of which region of the body? a) Cervical b) Thoracic c) Lumbar d) Thigh e) Arms

thigh

An individual with shingles presents with pain and lesions in the mouth, ears, and pharynx. Which dermatomal region would be sending the afferent signals? a) C2 b) C3 c) C1 d) trigeminal e) facial

trigeminal

Which type of descending motor pathway excites antigravity muscles in order to exert control over postural changes necessary to compensate for tilts and movements of the body.? a) vestibulospinal tract b) corticospinal tract c) corticobulbar tract d) spinothalamic tract e) gracile fasciculus

vestibulospinal tract