Exercise 20

Why do pain receptors function as tonic receptors?

Because tonic receptors constantly perceive the stimuli

When you extend the temperature beyond the level of cool and warm, the pain receptors in the skin are activated. Cool receptors are activated b/w 12 and 35 degrees C. Warm receptors are activated b/w 25 and 45 degrees C. You may have had an experience with very cold conditions. What perception is sensed?

Cool pain receptors

In terms of receptor density, describe why it is difficult to find the same location on the forearm when your eyes are closed

Due to the fact that there are not as many nerve endings in the forearm, it is harder to locate the precise location

An area with a great number of nerve endings is the upper lip. What can you predict about the ability of the upper lip to distinguish two points?

It will have strong capacity to distinguish between two points

Adaption occurs in some sensory stimulation. Why do you think this is important?

It's important because it is necessary for us to be able to adapt to our situations for example, the weather.

Distinguish among the functions of Pacinian corpuscles, Meissner corpuscles, and pain receptors in the skin

Pacinian corpuscles = sense pressure Meissner corpuscles = sense light touch Pain receptors = naked nerve endings that sense pain

Are there more cool receptors or warm receptors in the skin? What adaptive advantage might there be for an unequal number of receptors of one kind?

There are more warm receptors. allows us to adjust to the ever changing temperature conditions around us and be able to survive in the cold without feeling pain, and allows us to maintain body temperature

What kind of receptor determines the weight of an object when you pick it up?

baroreceptors or proprioceptors?

Meissner corpuscles respond to what kind of sensation?

light touch

In reference to the sense organs, what is modality?

no perception without environmental stimulus or input

Which kind of receptor (phasic/tonic) adapts to low light in a darkened movie theater?

phasic

what kinds of receptors are sensitive to the following modalities? light touch temperature sound smell

photoreceptors mechanoreceptors thermoreceptors mechanoreceptors chemoreceptors

when you drink a liquid that is burning hot, the "chest pain" felt in the region of the sternum does not really occur there. What kind of pain is this called?

referred pain

What kind of receptor is responsive to extremely hot sensations?

thermoreceptors