Lesson #2: Structure & Function: The Oral Cavity

Question 1

Oral Cavity

Answer 1

The process of ingestion takes
place in the oral cavity.

The oral cavity consists of the
mouth, teeth, pharynx,
epiglottis, salivary glands,
tongue and esophagus.

Question 2

The Mouth

Answer 2

The mouth consists of several
structures.

(A) Cheek – supports the oral cavity
and holds food

(B) Lips – keeps food in the mouth
during chewing

(C) Vestibule – the gap between the
lips and the gums

(F) Hard Palate – the “roof” of the
mouth supported by bone

(G) Soft Palate – the “roof” of the
mouth supported by skeletal muscle

Question 3

The Teeth

Answer 3

The primary agent of mechanical digestion in the
mouth.

Humans have two sets of teeth

20 deciduous (milk) teeth which are replaced
by 32 permanent (adult) teeth of which 12 are
molars.

Question 4

Regions of the Tooth

Answer 4

There are 3 general
regions of each tooth:

1. The Crown – the top of
   the tooth
2. The Neck – the central
   area of the tooth that
   contains the gums and
   nerve endings
3. The Root – area below
   the gums that contains
   the blood vessels and
   supporting structures

Question 5

Other Features of the Tooth

Answer 5

Enamel – covers the crown
of the tooth and is the
hardest substance in the
body.

Nerves – in the neck of the
tooth, they register
sensation (hot, cold, pain)

Pulp Cavity – a hollow tube
that runs through the middle
of the tooth that contains
blood vessels and nerve cells
Dentin – hard tissue that
supports the enamel and
contains no nerve endings

Periodontium – holds the
roots in the jaw

Cementum – bone with a
high concentration of
connective tissue

Question 6

Gums

Answer 6

Tissue that surrounds and
supports the teeth and
associated tissues

Also known as the gingiva

Question 7

Tonsils

Answer 7

Part of the immune system

Act as a filter for foreign material in the
mouth

Question 8

Pharynx

Answer 8

The muscle group that coordinates
swallowing.

Controls the intersection between
the digestive and respiratory system

Structures found in this area:

(U) Epiglottis – the flap of tissue
that prevents food from
entering the trachea

(S) Eustachian Tube – equalizes
pressure between the middle
ear, throat and nasal cavities

Question 9

Salivary Glands

Answer 9

There are 3 sets of salivary glands
(sublingual, submandibular and
parotid)

Produce Saliva

Saliva contains the enzyme
Salivary Amylase which
chemically breaks down starch
into glucose.

Saliva also contains enzymes
that clean the surfaces of the
mouth

Saliva is used to lubricate food

Question 10

Tongue

Answer 10

The primary organ of the
oral cavity

Made up of two parts:

The Root (O) – contains
a series of muscles and
nerve endings that link
the tongue to the
nervous system

The Body (N) – involved
in eating and drinking.
Surface covered with
Papillae (P) commonly
referred to as “taste
buds”