Review Questions

DIRECTIONS: Each of the numbered items or incomplete statements in this section is followed by answers or by completions of the statement. Select the ONE lettered answer or completion that is BEST in each case.

1. Which type of motor unit is of prime importance in generating the muscle power necessary for the maintenance of posture?

(A) Low threshold, fatigue-resistant

(B) High threshold, fatigable

(C) Intrafusal, gamma controlled

(D) High threshold, high force

(E) Extrafusal, gamma controlled

2. Which type of sensory receptor provides information about the force of muscle contraction?

(A) Nuclear bag fiber

(B) Nuclear chain fiber

(C) Golgi tendon organ

(D) Bare nerve ending

(E) Type Ia ending

3. If a patient experiences enlargement of the normally rudimentary central canal of the spinal cord in the midcervical region, which, if any, muscular functions would become abnormal first?

(A) Finger flexion

(B) Elbow flexion

(C) Shoulder abduction

(D) Truncal extension

(E) No muscles would become abnormal

4. Tapping the patellar tendon with a reflex hammer produces a brief contraction of the knee extensors. What is the cause of the muscle contraction?

(A) Elastic rebound of muscle connective tissue

(B) Golgi tendon organ response

(C) Muscle spindle activation

(D) Muscle spindle unloading

(E) Gamma motor neuron discharge

5. The cyclical flexion and extension motions of a leg during walking result from activity at which level of the nervous system?

(A) Cerebral cortex

(B) Cerebellum

(C) Globus pallidus

(D) Red nucleus

(E) Spinal cord

6. Which brainstem-derived descending tract produces action similar to the corticospinal tract?

(A) Vestibulospinal

(B) Reticulospinal

(C) Spinocerebellar

(D) Rubrospinal

7. What is the location of the primary motor area of the cerebral cortex?

(A) Upper parietal lobe

(B) Superior temporal lobe

(C) Precentral gyrus

(D) Postcentral gyrus

(E) Medial aspect of the hemisphere

8. Concurrent flexion of both wrists in response to electrical stimulation is characteristic of which area of the nervous system?

(A) Postcentral gyrus

(B) Vestibulospinal tract

(C) Dentate nucleus

(D) Primary motor cortex

(E) Supplementary motor cortex

9. If you could histologically examine the spinal cord of a patient who had experienced a viral illness 10 years before in which only the neurons of the primary motor area of the cerebral cortex were destroyed, what findings would you expect?

(A) The corticospinal tract would be completely degenerated

(B) The rubrospinal tract would show an increased number of axons

(continued)

(C) The corticospinal tract would be about one-third depleted of axons

(D) The alpha motor neurons would be atrophic

(E) The corticospinal tract would be normal

10.A disease that produces decreased inhibitory input to the internal segment of the globus pallidus should have what effect on the motor area of the cerebral cortex?

(A) Increased excitatory feedback directly to the cortex

(C) Decreased excitatory output from the thalamus to the cortex

(D) Increased excitatory output from the putamen to the cortex

(E) Increased excitatory output from the thalamus to the cortex ll.Which cerebellar component would be abnormal in a degenerative disease that affected spinal sensory neurons?

(A) Purkinje cells

(B) Mossy fibers

(C) Parallel fibers

(D) Climbing fibers

(E) Granule cells

Was this article helpful?

+1 0
Essentials of Human Physiology

Essentials of Human Physiology

This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.

Get My Free Ebook


Responses

  • fastred
    Which type of sensory receptor provides information about the force ofmuscle contraction?
    1 year ago

Post a comment