Biology 12

Chapter 5 The Nervous System • MHR 159

Exploring Further

5.Use sources such as other texts, reference books,

or the Internet to match the labels below to the

numbers in the diagram. Record the function of

each part.

auditory canal pinna

auditory tube round window

cochlea semicircular canals

cochlear nerve stapes

incus (anvil) tympanic membrane

malleus (hammer) vestibule

oval window vestibular nerve

6.The ear contains structures that provide information

to the cerebellum to maintain equilibrium. Use

resources other than this textbook to answer the

following questions.

(a)What parts of the ear are used to maintain

equilibrium?

(b)What is the difference between dynamic and

static equilibrium?

(c)Explain which parts of the ear are responsible for

dynamic equilibrium and which are responsible

for static equilibrium. Describe how these

structures work.

OUTER EAR

MIDDLE

EAR INNER EAR

8

9

10

11

12

14 13

1

2

3

(^456)
7
epidermis
dermis
free nerve endings
(pain, heat, cold)
Merkel discs
(touch)
Krause end bulbs
(touch)
Meissner’s corpuscles
(touch)
Pacinian corpuscles
(pressure)
Ruffini endings
(pressure, stretching)
Figure 5.19This classic
view shows each receptor
as having the main function
indicated. However,
scientific investigations
indicate that matters are not
so clear-cut. For example,
microscopic examination of
the skin of the ear shows
only free nerve endings
(pain receptors), and yet the
skin of the ear is sensitive to
all sensations. Therefore, it
appears that the receptors
of the skin are somewhat,
but not completely,
specialized.