Fundamentals of Anatomy and Physiology

384

Soft palate

is pressed

against back

of pharynx

Food bolus (^)
(^) Air (^)
(^) Tongue (A) (^)
(^) Soft palate (^)
(^) Pharynx (^)
(^) Epiglottis (^)
(^) Larynx
Epiglottis
(^)
tips down, (^)
closing (^)
(^) Trachea (^) ® windpipe (^)
(^) Learning
(^)
(^) Esophagus
Cengage
(B)
(^) ©
Figure 16- 7 The swallowing sequence into the
esophagus.
Chapter 16
(^) ®
Learning
Cengage ©
Soft palate
relaxes
Epiglottis^
raised
Contraction of^
®^ esophageal^
®^
Learning
(^) muscles propels
Learning^
food toward
stomach
Cengage
Cengage^

©^ (C)^

©^

Common Disease, Disorder, or Condition

Cavities and Tooth Decay

Dental caries (tooth decay) form at the tooth surface in areas where bacteria and food

debris accumulate and remain undisturbed for prolonged periods. These -areas are

usually the pits and grooves of molar teeth, between the teeth, and in the area of the

gumline. A tooth cavity is produced by the action of bacteria on carbohydrate food

residues with the production of acids that can dissolve the enamel. To prevent decay,

tooth brushing should be done immediately after eating, when possible, to exert its

greatest effort in destroying acid formation. In addition, daily flossing removes- food

deposits from between the teeth along the gumline.

the uvula to move upward and close off the nasophar-
ynx (nay-zoh-FAIR-inks). Now the larynx is pulled for-
ward and upward under the tongue where it meets the
epiglottis and seals off the glottis (the common opening

into the trachea). The food bolus passes through the la-

ryngopharynx and enters the esophagus in about 1 sec-ond.

The respiratory passageways reopen and breathing

resumes.