HUMAN BIOLOGY

SenSory SyStemS 283

2. Name six categories of sensory receptors and the type of
   stimulus that each type detects.


3. How do somatic sensations differ from special senses?


4. Explain where free nerve endings are located in the body
   and note some functions of the various kinds.


5. What is pain? Describe one type of pain receptor.


6. What are the stimuli for taste receptors?


7. How do “smell” signals arise and reach the brain?


8. Label the parts of the ear:

© Cengage Learning

© Cengage Learning

© Cengage Learning

Category Examples Stimulus

Mechanoreceptors

Touch, pressure Certain free nerve endings and Mechanical pressure against body surface

Merkel’s discs in skin

Baroreceptors Carotid sinus (artery) Pressure changes in blood

Stretch Muscle spindle in skeletal muscle Stretching of muscle

Auditory Hair cells in organ inside ear Vibrations (sound waves)

Balance Hair cells in organ inside ear Fluid movement

Thermoreceptors Certain free nerve endings (heating, cooling) Change in temperature

nociceptors Certain free nerve endings Tissue damage (e.g., distortions, burns)

(pain receptors)

Chemoreceptors

Internal chemical sense Carotid bodies in blood vessel wall Substances (O 2 , CO 2 , etc.) dissolved in extracellular fluid

Taste Taste receptors of tongue Substances dissolved in saliva, etc.

Smell Olfactory receptors of nose Molecules in air

osmoreceptors Hypothalamic osmoreceptors Change in water volume (solute concentration) of fluid

around them

Photoreceptors

Visual Rods, cones of eye Wavelengths of light

Table 14.3 Animated! Summary of Major Types of Sensory Receptors

11. How does the eye focus the light rays of an image? What
    do nearsighted and farsighted mean?

seLF-Quiz Answers in Appendix VI

1. A is a specific form of energy that can elicit a
   response from a sensory receptor.


2. Awareness of a stimulus is called a.


3. is understanding what particular sensations mean.


4. A sensory system is composed of.
   a. nerve pathways from specific receptors to the brain
   b. sensory receptors
   c. brain regions that deal with sensory information
   d. all of the above


5. detect energy associated with changes in pressure,
   body position, or acceleration.
   a. Chemoreceptors c. Photoreceptors
   b. Mechanoreceptors d. Thermoreceptors


6. Label the parts of the eye:


7. In the ear, sound waves cause the tympanic membrane
   to vibrate. What happens next in the middle ear? In the
   inner ear?

Copyright 2016 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s).