Essentials of Anatomy and Physiology

for lunch he decided that he didn’t mind it at all.

Explain what happened, and why his mother did

mind.

3. When we are out in very cold weather, why don’t
   our eyes freeze shut? Try to think of two reasons.


4. You probably have at one time hit your “funny
   bone,” which is really the ulnar nerve where it
   crosses the elbow. Such a whack is very painful, and
   not just in the elbow but all the way down the fore-
   arm to the ring and little fingers of the hand. This
   is referred pain. Explain why it happens, and name
   the characteristic of sensations that it illustrates.


5. Albinism is a genetic characteristic in which
   melanin is not produced; it may occur in just
   about any type of animal. As you probably know,
   an albino person will have white skin and hair.
   Describe the consequences for the person’s
   eyes.


6. We sometimes hear that blind people have a better
   sense of hearing than do sighted people. Do you
   think this is really true? Explain. Name two other
   senses a blind person may especially depend upon.
   Explain.


7. Look at Question Figure 9–A. In part A, which rec-
   tangle seems wider, the upper one or the lower
   one? Measure them, and explain your answer. Part
   B shows a Necker cube. Look at the cube and let

your eyes relax. What seems to happen? Why do

you think this happens? Part C has some lines and

some shaded blocks. But what do we see? Explain.

8. Look at Question Figure 9–B. Part A shows a nor-
   mal visual field. Parts B, C, and D are the visual
   fields of eye disorders you have read about in this
   chapter. Try to name each, with a reason for your
   answer.

220 The Senses

A Normal

B

C

D

Question Figure 9–B

A B

C

Question Figure 9–A