Digestive System

Question 1

Describe the general function of the Digestive System.

Answer 1

To change complex organic nutrient molecules into simple organic and inorganic molecules to be absorbed and transported to the cells.

Question 2

Name the divisions of the digestive system and the organs that comprise them.

Answer 2

Alimentary tube

• oral cavity
• pharynx
• esophagus
• stomach
• small intestine
• large intestine Accessory organs
• teeth
• tongue
• salivary glands
• liver
• bile
• gall bladder
• pancreas

Question 3

Define the function of the teeth.

Answer 3

Mastication

Question 4

Explain how the tongue assists with digestion.

Answer 4

It mixes food during chewing, forms it into a bolus, and initiates swallowing.

Question 5

Explain the function of salivary glands.

Answer 5

Moistens and aids compaction into a bolus and contains enzymes to breakdown starchy foods.

Question 6

Explain the function of bile and state where it is stored.

Answer 6

Bile is stored in the liver and gall bladder. Contains acids for digestion and absorption in the small intestine. Contains many waste products from the body.

Question 7

What role does the pancreas play in digestion?

Answer 7

Aids in acid reduction of chyme as it travels from the stomach to the small intestine. Helps break down proteins, fats, and starch to be absorbed.

Question 8

Define mechanical digestion.

Answer 8

The physical breaking up of food into smaller pieces.

Question 9

Define chemical digestion.

Answer 9

The use of enzymes to break down complex chemical molecules into simpler chemicals that can be utilized by the body.

Question 10

Define deciduous teeth.

Answer 10

baby teeth, 20

Question 11

How many permanent teeth are there?

Answer 11

32

Question 12

List the parts of a tooth and their location.

Answer 12

• Crown - visible part of tooth above the gingiva
• Enamel - outer part of the crown, hardest part of the body
• Dentin - inside the enamel and root, similar to bone
• Pulp cavity - innermost part of tooth containing blood vessels and nerves
• Periodontal membrane - lines the tooth socket and anchors the tooth

Question 13

Explain the function of saliva.

Answer 13

• cleans teeth
• dissolves food chemicals so they can be tasted
• moistens food to aid in bolus formation
• contains enzymes to breakdown starchy foods

Question 14

Explain the function of the pharynx in digestion.

Answer 14

Its only function is swallowing.

Question 15

Explain the function fo the esophagus in digestion.

Answer 15

It takes food from the pharynx to the stomach.

Question 16

State the location and function of the lower esophageal sphincter.

Answer 16

Located at the junction of the esophagus and the stomach. Opens to allow food into the stomach then closes to keep stomach contents out of the esophagus.

Question 17

State the functions of mucosa of the alimentary canal.

Answer 17

• secretion of mucus
• absorption of nutrients
• protection against disease

Question 18

State the functions of submucosa of the alimentary canal.

Answer 18

• supplies surrounding tissue with blood and lymphatic vessels
• regulates secretions

Question 19

State the functions of the external muscle layer of the alimentary canal.

Answer 19

• propel and mix food along the digestive tract

* forms sphincters that act as valves to prevent backflow

Question 20

Define the serosa of the alimentary canal.

Answer 20

The outermost layer of the alimentary canal. Also called the visceral peritoneum.

Question 21

List the parts of the stomach.

Answer 21

• lower esophageal sphincter
• fundus
• body
• pylorus
• pyloric sphincter
• contains rugae

Question 22

Define rugae.

Answer 22

Folds in the stomach that allow for expansion.

Question 23

State the general function of the stomach.

Answer 23

A sac that extends from the esophagus to the small intestines. Serves a reservoir for food. Both mechanical and chemical digestion occur in the pylorus.

Question 24

Define gastric pits.

Answer 24

glands in the stomach that secrete gastric juice

Question 25

Define chyme.

Answer 25

creamy semifluid mass of ingested food that leaves the stomach

Question 26

Define instrinsic factor.

Answer 26

Secretion of the stomach that is required for the intestinal absorption of vitamin B12.

Question 27

List the substances absorbed by the stomach.

Answer 27

* water * alcohol * aspirin

Question 28

Explain the function of the small intestine.

Answer 28

Virtually all absorption of nutrients takes place.

Question 29

Explain the function of the large intestine.

Answer 29

Absorption of water, minerals, and vitamins and the elimination of indigestible material. 80% of the water that enters the large intestine is absorbed.

Question 30

Describe the function of the normal flora in the colon.

Answer 30

Produce vitamins aborbed by the colon.  Inhibits the growth of pathogens.  

Question 31

Define peristalsis.

Answer 31

The contracting and relaxing of muscles in the digestive tract to propel food.

Question 32

Explain how food is broken down into chemical components.

Answer 32

* carbohydrates to simple sugars * proteins to amino acids * fats to fatty acids and glycerol

Question 33

Where does absorption of nutrients occur?

Answer 33

From the lumen in the small intestine into the vessels within the villi.

Question 34

Where does the blood from the capillary network in the villi go before going back to the heart?

Answer 34

The portal vein to the liver.

Question 35

Locate and define the greater omentum.

Answer 35

Enormous pouch of the visceral peritoneum of the stomach that hangs from the greater curvature of the stomach. It protects the abdominal viscera.

Question 36

Locate and define the lesser omentum.

Answer 36

Extends from the lesser curvature of the stomach to the liver and connects them.