Ap 1 Lab Ex 25 Answers
Exercise 25
Special Senses: Hearing and Equilibrium
Answers to Pre-Lab Quiz (pp. 383–384)
1. three
2. a, auricle
3. tympanic membrane
4. d, stapes
5. a, cochlea
6. otoscope
7. b, Rinne
8. b, internal ear
9. macula/vestibule
10. c, involuntary trailing of eyes in one direction, then rapid movement in the other
Answers to Activity Questions
Activity 4: Conducting Laboratory Tests of Hearing (pp. 387–388)
Acuity Test
The threshold is indefinite.
Sound Localization
No, the sound is less easily located if the source is equidistant from both ears. Sound arriving from spots equidistant from both ears arrives at each ear at the same time and with equal loudness. This does not provide enough information to adequately locate the position of the source.
Frequency Range of Hearing
Generally, high-frequency sounds are heard less clearly, but results depend on the loudness of each of the tuning forks.
Activity 7: Conducting Laboratory Tests on Equilibrium (pp. 391–392)
Balance Test
1. Nystagmus should not be present.
2. The cerebellum integrates input from receptors in the vestibule and semicircular canals, the eyes and somatic receptors, and coordinates skeletal muscle activity and regulates muscle tone.
Barany Test
4. When rotation stops, the direction of nystagmus reverses. If the chair is rotated clockwise, the nystagmus will be counterclockwise. For a few seconds after the chair is stopped, the subject reports a feeling of movement in the same direction and the same speed in which the chair was spun.
Romberg Test
2. Gross swaying movements are not usually observed when the eyes are open.
3. Side-to-side movement increases.
4. Front-to-back swaying occurs. The equilibrium apparatus and proprioceptors are probably functioning normally. Visual information is lacking and the result is increased swaying. Equilibrium and balance require input from a number of receptors, including proprioceptors, the vestibular apparatus, and the eyes.
Review Sheet
Exercise 25
Special
Special Senses: Hearing and Equilibrium
Answers to Pre-Lab Quiz (pp. 383–384)
1. three
2. a, auricle
3. tympanic membrane
4. d, stapes
5. a, cochlea
6. otoscope
7. b, Rinne
8. b, internal ear
9. macula/vestibule
10. c, involuntary trailing of eyes in one direction, then rapid movement in the other
Answers to Activity Questions
Activity 4: Conducting Laboratory Tests of Hearing (pp. 387–388)
Acuity Test
The threshold is indefinite.
Sound Localization
No, the sound is less easily located if the source is equidistant from both ears. Sound arriving from spots equidistant from both ears arrives at each ear at the same time and with equal loudness. This does not provide enough information to adequately locate the position of the source.
Frequency Range of Hearing
Generally, high-frequency sounds are heard less clearly, but results depend on the loudness of each of the tuning forks.
Activity 7: Conducting Laboratory Tests on Equilibrium (pp. 391–392)
Balance Test
1. Nystagmus should not be present.
2. The cerebellum integrates input from receptors in the vestibule and semicircular canals, the eyes and somatic receptors, and coordinates skeletal muscle activity and regulates muscle tone.
Barany Test
4. When rotation stops, the direction of nystagmus reverses. If the chair is rotated clockwise, the nystagmus will be counterclockwise. For a few seconds after the chair is stopped, the subject reports a feeling of movement in the same direction and the same speed in which the chair was spun.
Romberg Test
2. Gross swaying movements are not usually observed when the eyes are open.
3. Side-to-side movement increases.
4. Front-to-back swaying occurs. The equilibrium apparatus and proprioceptors are probably functioning normally. Visual information is lacking and the result is increased swaying. Equilibrium and balance require input from a number of receptors, including proprioceptors, the vestibular apparatus, and the eyes.
Review Sheet
Exercise 25
Special