Digestive System I

Question 0

List the six functions of the digestive system.

Answer 0

1. Ingestion
2. Digestion
3. Propulsion
4. Secretion
5. Absorption
6. Excretion

Question 1

Describe the path that food follows through the alimentary canal.

Answer 1

Oral cavity
pharynx
esophagus
stomach
small intestine
large intestine

Question 2

What are the six accessory digestive organs?

Answer 2

1. Teeth
2. Tongue
3. Salivary glands
4. Liver
5. Gallbladder
6. Pancreas

Question 3

What are the two types of food propulsion?

Answer 3

Peristalsis

Segmentation

Question 4

List the major digestive structures of the oral cavity.

Answer 4

1. Cheeks, lips and palate
2. Tongue
3. Salivary glands
4. Teeth

Question 5

What are the anatomical abnormalities and complications of cleft palate?

Answer 5

Incomplete formation of the two halves of the hard and soft palate during gestation. Complications include feeding difficulty, ear infections, hearing loss, speech and language delay, and dental problems.

Question 6

What accessory digestive organs are involved in forming a bolus?

Answer 6

The cheeks, lips, palate, tongue, teeth and Savilary glands.

Question 7

What are the functions of saliva? Locate the 3 Savilary glands and describe the two types of cells that contain.

Answer 7

1. Moistens food to form a bolus
2. Moistens and cleans the mouth
3. Chemical digestion (Savilary amylase begins carb breakdown)
4. Antibacterial action
5. Dissolves food for taste

Parotid, submandibular, sublingual

Mucous cells and serous cells

Question 8

What is mumps?

Answer 8

A common childhood disease characterized by inflammation of the parotid gland; virus spread by saliva.

Question 9

What is the major function of each of the four types of permanent teeth?

Answer 9

1. Incisors: cutting and slicing
2. Canines: puncturing and tearing
3. Premolars: crushing and grinding
4. Molars: crushing and grinding

Question 10

Which regions of the pharynx are utilized by the digestive system? How is food kept out of the respiratory pathway (both the nasal cavity and the larynx)?

Answer 10

oropharynx and laryngopharynx; uvula and epiglottis

Question 11

Which kind of epithelial tissue do you expect to find in the initial portions of the digestive pathway?

Answer 11

Non-keratinized stratified squamous epithelium

Question 12

Name the esophageal sphincters. What is the primary structure in preventing acid reflux (hint: not actually an esophageal sphincter)?

Answer 12

Superior esophageal sphincter and inferior esophageal sphincter; the esophageal hiatus

Question 13

Describe the steps of swallowing, be sure to differentiate voluntary from involuntary stages.

Answer 13

Voluntary phase: Bolus of food is pushed by the tongue against hard palate and then moves towards oropharynx.

Pharyngeal phase: (involuntary) As bolus moves into oropharynx, the soft palate and uvula close off nasopharynx, and the larynx elevates so the epiglottis closes over laryngeal opening.

Esophageal phase: (involuntary) peristaltic contractions of the esophageal muscle push bolus toward stomach; soft palate, uvula, and larynx return to their pre-swallowing positions.

Question 14

How many layers of muscle does the stomach have? Why? What type of muscle is it?

Answer 14

The stomach possesses three layers of muscle to aid in the mechanical processing of ingested materials; Smooth muscle

Question 15

The bolus is eventually processed into a pastelike soup called what?

Answer 15

Chyme

Question 16

How long does food stay in the stomach?

Answer 16

Four hours

Question 17

What are the four regions of the stomach?

Answer 17

1. Cardia
2. Fundus
3. Body
4. Pylorus

Question 18

How much food absorption occurs in the stomach?

Answer 18

Very little

Question 19

What are the depressions lining the stomach called?

Answer 19

Gastric pits

Question 20

What are the three layers of muscle in the stomach wall called?

Answer 20

1. Longitudinal layer
2. Circular layer
3. Oblique layer

Question 21

What are the five types of secretory cells in the gastric pits?

Answer 21

1. Surface mucous cells
2. Mucus neck cells
3. Parietal cells
4. Chief or peptic cells
5. Enteroendocrine cells

Question 22

What is the primary function of the stomach?

Answer 22

To continue the mechanical and chemical digestion of the bolus.

Question 23

What are the causes, symptoms, and treatments of an ulcer? Where is an ulcer most commonly found?

Answer 23

Causes: environment too acidic, stress, aspirin, 80% associated with bacterium.

Symptoms: burning pain and epigastric region, nausea, vomiting, and bleeding.

Treatments: antibiotics and acid reducing drugs, diet

Ulcers are most commonly found in the duodenum.