16.2 Mouth

Question 1

What is the other name of the mouth?

Answer 1

Oral cavity

Question 2

What forms the opening of the mouth

Answer 2

muscular lips

Question 3

What is the function of lips?

Answer 3

It helps procure, guide, and contain the food in the mouth

Question 4

The palate forms the?

Answer 4

arched roof of the oral cavity

Question 5

What is the function of the palate?

Answer 5

It separates the mouth from the nasal passage allowing for breathing and chewing or sucking to take place simultaneously

Question 6

Where is the uvula located

Answer 6

it hangs from the palate in the rear of the throat

Question 7

What is the function of the uvula?

Answer 7

To close the nasal passage during swallowing

Question 8

The floor of the oral cavity is formed by?

Answer 8

the tongue

Question 9

What type of muscle does the tongue have?

Answer 9

Skeletal muscle (voluntary)

Question 10

What is the function of the tongue?

Answer 10

It guides food within the mouth during chewing and swallowing and also plays a role in speech.

Question 11

Where are the taste buds located and what are their function?

Answer 11

they are located on the tongue and have a role of providing the sense of taste.

Question 12

What is the function of teeth?

Answer 12

To mechanically break down food

Question 13

What is the first step in the digestion process and explain it

Answer 13

Mastication (chewing): mouth motility that involves tearing, slicing, grinding and mixing of ingested food by the teeth.

Question 14

where are teeth embedded and protruding from?

Answer 14

the jawbones

Question 15

What is occlusion?

Answer 15

it is how well the upper and lower teeth fit together when the jaw is closed.

Question 16

what is the most important factor when determining the efficiency of chewing?

Answer 16

occlusion

Question 17

What is malocclusion?

Answer 17

It is when the upper and lower teeth do not make proper contact with one another hence they cannot accomplish normal cutting and grinding.

Question 18

What causes malocclusion and what can fix it?

Answer 18

It can be caused by overcrowding of teetgh or displacement of the jaw. This can be rectified by braces

Question 19

What covers the exposed part of the tooth and is considered the hardest structure of the body?

Answer 19

Enamel

Question 20

Enamel cannot be regenerated so any teeth defects that occur in the enamel must be………….

Answer 20

patched by artificial filings or else the surface will continue to erode into the underlying living pulp.

Question 21

The act of chewing can be voluntary but……….

Answer 21

Most chewing during a meal is a rhythmic reflex-like activity accomplished without conscious effort.

Question 22

What are the three functions of chewing?

Answer 22

1. To mechanically break down food into smaller pieces to facilitate swallowing and to increase the food surface area on which salivary enzymes can act.
2. To mix food with saliva
   3.To expose food to taste buds

Question 23

What are the 2 functions of taste bud stimulation?

Answer 23

1. gives the pleasurable sensation of taste
2. it reflexly increases salivary,gastric,pancreatic, and bile secretions to prepare for the arrival of food

Question 24

What type of digestion begins in the mouth due to salivary amylase?

Answer 24

Carbohydrate digestion

Question 25

What produces saliva?

Answer 25

The three salivary glands that secrete saliva into the mouth by their short ducts.

Question 26

What is the composition of saliva?

Answer 26

99.5% water , 0.5% electrolytes and protein

Question 27

How much saliva is secreted daily?

Answer 27

1-2 L

Question 28

What are the three most important salivary proteins?

Answer 28

salivary amylase, mucus and lysozymes.

Question 29

What are the 3 salivary glands and their locations?

Answer 29

1. Sublingual gland- under the tongue on the floor of the mouth
2. Submandibular gland-beneath the mandible
3. Parotid gland- Situated in front of and just below each ear, on the sides of the face. (largest)

Question 30

List the 7 functions of saliva:

Answer 30

1. Digestion of starches (breaks down dietary carbs into maltose and a-limit dextrins)
2. Facilitates swallowing
3. Antibacterial action
4. Solvent for taste molecules
5. Aids in speech
6. Oral hygiene
7. Dental protection

Question 31

Despite the many functions of saliva………………..

Answer 31

It is not required for digestion and absorption because the pancreatic and small intestine are more than capable of performing digestion without salivary and gastric secretions.

Question 32

What is xerostomia

Answer 32

it is a condition characterised by dry mouth due to diminished salivary secretion. This causes difficulty in chewing and swallowing, inarticulate speech unless there are frequent sips of water taken when speaking, and an increase in dental cavities unless special precaution is taken.

Question 33

In the absence of food-related stimuli, what other factor stimulates salivary secretion?

Answer 33

Low-level parasympathetic stimulation induces production of basal salivary secretion

Question 34

what is the importance of basal salivary secretion?

Answer 34

It ensures that the mouth and throat are always lubricated.

Question 35

Besides food stimulation and parasympathetic stimulation, what other two reflexes stimulate the secretion of saliva?

Answer 35

Simple reflex and conditioned reflex

Question 36

Explain simple salivary reflex?

Answer 36

This is when chemoreceptors and pressure receptors within the oral cavity respond to the presence of food. They then initiate impulses in afferent nerve fibers which carry this information to the salivary center in the medulla oblongata. The salivary center in turn sends impulses via the extrinsic autonomic nerve to the salivary glands to promote increased salivation.

Question 37

Why do we salivate so much during dental procedures?

Answer 37

Due to pressure receptors being activated

Question 38

Explain conditioned salivary reflex?

Answer 38

It occurs without oral stimulation but rather due to the stimulation of the other senses. This reflex is a learned response. The cerebral cortex processes the sensory input and then stimulates the medulla oblongata salivary center which sends impulses to the salivary glands to increase salivation via the autonomic nerves.

Question 39

What does the salivary center do?

Answer 39

it controls the degree of salivary output by means of the autonomic nerves that supply the salivary glands.

Question 40

What is different about sympathetic and parasympathetic stimulations when it comes to salivary compared to other parts of the body

Answer 40

They are not antagonistic! Rather both of them increase salivary secretions but the difference is that the quantity and characteristics differ.

Question 41

Explain parasympathetic stimulation of salivating

Answer 41

It exerts the dominant role in salivary secretion, it produces a prompt abundant flow of watery saliva rich in enzymes.

Question 42

Explain sympathetic stimulation of salivating

Answer 42

It produces a smaller volume of thick saliva rich in mucus. It is for this reason that the mouth feels drier when it is dominant during a fight or flight response.

Question 43

Salivary secretion is the only digestive secretion entirely under…………..

Answer 43

neural control

Question 44

Where does the majority of the function of salivary amylase occur?

Answer 44

In the stomach after the food and saliva have been swallowed and before HCl inactivates it in between the food mass.