The spiral organ, in the
inner ear, has rows of hair
cells, each bearing up to
100 hairs, which translate
sound into neural
messages that travel to
the brain (2,700
After you have studied this chapter, you should be able to:
erentiate between general senses and special senses.
12.2 Receptors, Sensation, and Perception
Name the F
ve types o± receptors and state the ±unction o± each.
Explain how receptors stimulate sensory impulses. (p. 439)
Explain sensation production and adaptation. (p. 439)
12.3 General Senses
Describe the dif
erences among receptors associated with the senses
o± touch, pressure, temperature, and pain. (p. 440)
Describe how the sensation o± pain is produced. (p. 440)
Explain the importance o± stretch receptors in muscles and tendons.
12.4 Special Senses
Explain the relationship between the senses o± smell and taste.
Describe how the sensations o± smell and taste are produced and
interpreted. (p. 446)
Name the parts o± the ear and explain the ±unction o± each part.
Distinguish between static and dynamic equilibrium. (p. 459)
Describe the roles o± the accessory organs to the eye. (p. 462)
Name the parts o± the eye and explain the ±unction o± each part.
Explain how the eye re±racts light. (p. 471)
Explain how the brain perceives depth and distance. (p. 475)
Describe the visual nerve pathways. (p. 475)
12.5 Life-Span Changes
Describe aging-associated changes that diminish the senses. (p. 476)
itory—pertaining to hearing.
coat—middle, vascular layer o± the eye.
—coiled tube in the inner ear.
ea—transparent outer layer in the anterior
portion o± the eye.
—colored, muscular part o± the eye.
—complex system o± connecting
chambers and tubes o± the inner ear.
mal gland—tear gland.
ea—yellowish spot on the retina.
lutea—yellowish spot on the retina.
us—one o± the three bones in the middle
i—muscle associated with the eyelid.
ory—pertaining to the sense o± smell.
associated with the eyelid.
receptors—specialized structures in the eye
responsive to light.
a—tough, outer protective layer o± the eye.
oreceptor—receptor sensitive to changes in
ous humor—clear, jellylike substance within the