Digestive System

Question 1

Which accessory organs assist in the mechanical breakdown of food?

Answer 1

The teeth: they cut and grind down food.

Question 2

What is the function of the nerves in the wall of the gastrointestinal tract?

Answer 2

Nerves in its wall help regulate secretions and contractions of the GI tract.

Question 3

Which part of the peritoneum binds the small intestine to the posterior abdominal wall?

Answer 3

Mesentery binds the small intestine to the posterior abdominal wall.

Question 4

What are the functions of the muscles of the tongue?

Answer 4

Maneuver food for chewing, shape food into a bolus, force food to the back of the mouth for swallowing, and alter the shape of the tongue for swallowing and speech production.

Question 5

What type of tissue is the main component of teeth?

Answer 5

A connective tissue called dentin.

Question 6

Is swallowing a voluntary action or an involuntary action?

Answer 6

Both. Initiation of swallowing is voluntary. Completion of swallowing (esophagus to stomach) is involuntary involving peristalsis of smooth muscle.

Question 7

Does your stomach still have rugae after a very big meal?

Answer 7

Probably not because as the stomach fills the rugae stretches out.

Question 8

Which stomach layer is in contact with swallowed food?

Answer 8

The simple columnar epithelial cells of the mucosa.

Question 9

What substances are present in pancreatic juice?

Answer 9

A mixture of water, salts, bicarbonate ions, and digestive enzymes.

Question 10

Which cells in the liver are phagocytes?

Answer 10

Stellate reticuloendothelial cells in the liver.

Question 11

In which quadrant is most of the ileum located?

Answer 11

Lower right quadrant (refer to fig 19.11)

Question 12

Where are the cells that absorb dietary nutrients located?

Answer 12

In the mucosal epithelium

Question 13

How are fat soluble vitamins (A, D, E and K) absorbed?

Answer 13

By diffusion from micelles

Question 14

What are the functions of the large intestine?

Answer 14

Completion of absorption, synthesis of certain vitamins, formation of feces, and elimination of feces.

Question 15

How does the muscularis of the large intestine differ from that of other parts of the GI tract?

Answer 15

It forms longitudinal bands (teniae coli) that gather the colon into a series of pouches.

Question 16

The __ __ is a tube open at both ends extending from mouth to the anus. Functions to transit food during its processing.

Answer 16

Gastrointestinal tract

Question 17

The 6 functional segments of the GI tract include:

Answer 17

Mouth, esophagus, small intestine, pharynx, stomach, and large intestine.

Question 18

The 6 accessory structures of the GI tract include:

Answer 18

Teeth, salivary glands, gallbladder, tongue, liver, and pancreas.

Question 19

What are the 6 functions of the digestive system?

Answer 19

Ingestion, secretion, mixing and propulsion, digestion, absorption, and defecation.

Question 20

__ is taking food into the mouth (eating).

Answer 20

Ingestion

Question 21

__ is the release by cells within the walls of the GI tract and accessory organs - water, acid, buffers, enzymes into the lumen of the tract.

Answer 21

Secretion

Question 22

__ and __ are caused by the alternating contraction and relaxation of the smooth muscles within the walls of the GI tract.

Answer 22

Mixing and propulsion

Question 23

__ both mechanical and chemical, breaks ingested food into small molecules.

Answer 23

Digestion

Question 24

__ is the passage of the end products of digestion from the GI tract into blood or lymph for distribution to cells.

Answer 24

Absorption

Question 25

__ is the emptying of the rectum, which eliminates indigestible substances from the GI tract.

Answer 25

Defecation

Question 26

The basic arrangement of layers in the GI tract, from the inside outward includes:

Answer 26

Mucosa, submucosa, muscularis, and serosa (visceral peritoneum)

Question 27

The potential space between the parietal and visceral portions of the peritoneum is called the __ __, which contains serous fluid.

Answer 27

Peritoneal cavity

Question 28

Some organs such as the kidneys and pancreas lie on the posterior abdominal wall behind the peritoneum; these organs are called __ .

Answer 28

Retroperitoneal

Question 29

The 3 pairs of salivary glands are:

Answer 29

Parotid, submandibular (submaxillary), and sublingual glands

Question 30

The __ is a funnel shaped tube that extends from the internal nares to the esophagus posteriorly and the larynx anteriorly.

Answer 30

Pharynx

Question 31

The __ is a collapsible, muscular tube lying behind the trachea that connects the pharynx to the stomach.

Answer 31

Esophagus

Question 32

What is peristalsis?

Answer 32

Propulsive contractions

Question 33

The __ is a J-shaped enlargements of the GI tract that begins at the bottom of the esophagus and ends at the pyloric sphincter.

Answer 33

Stomach

Question 34

When a bolus is converted to a liquid it is called __

Answer 34

Chyme

Question 35

The gross anatomical subdivisions of the stomach include the following:

Answer 35

Cardia, fundus, body, pylorus.

Question 36

When the stomach is empty, the mucosa lies in folds called __.

Answer 36

Rugae

Question 37

The surface of the mucosa is a layer of simple columnar epithelial cells called __ __ __.

Answer 37

Surface mucous cells

Question 38

The gastric glands consist of 3 types of exocrine glands:

Answer 38

Mucous neck cells (secrete mucous), chief cells (secrete pepsinogen and gastric lipase), and parietal (secrete HCl).

Question 39

Mechanical digestion consists of peristaltic movements called __ __.

Answer 39

Mixing waves

Question 40

__ __ is the periodic release of chyme from the stomach into the duodenum.

Answer 40

Gastric emptying

Question 41

Pancreatic acini secrete a mixture of fluid and digestive enzymes called __ __.

Answer 41

Pancreatic juice

Question 42

The __ is a sac located in a depression on the posterior surface of the liver.

Answer 42

Gallbladder

Question 43

__ is partially an excretory product and partially a digestive secretion.

Answer 43

Bile

Question 44

The small intestine is divided into the following parts:

Answer 44

Duodenum, jejunum, and ileum.

Question 45

Projections called __ folds or __ circulares are permanent ridges in the mucosa that enhance absorption by increasing surface area and causing chyme to spiral as it passes through the small intestine.

Answer 45

Circular folds; plicae circulares

Question 46

The cells of the mucosal (simple columnar) epithelium include the following 3 cells:

Answer 46

Absorptive cells, goblet cells (mucous secreting), and endocrine cells (hormone producing).

Question 47

What are the 3 phases of digestion?

Answer 47

Cephalic phase, gastric phase, and intestinal phase.

Question 48

Explain the cephalic phase of digestion.

Answer 48

Secretion of saliva and gastric juice in response to the sight, smell, sound, or thought of food.

Question 49

Explain the gastric phase of digestion.

Answer 49

Food enters the stomach; gastric juice secretion is promoted by the hormone gastrin; chyme leaves the stomach.

Question 50

Explain the intestinal phase of digestion.

Answer 50

Chyme enters the small intestine; gastric emptying is inhibited, mechanical and chemical digestion in the small bowel is promoted; acidity of chyme buffered.

Question 51

__ is the major movement of the small intestine, is a localized contraction in areas containing food.

Answer 51

Segmentation

Question 52

__ is the passage of the end products of digestion from the GI tract into blood or lymph, and occurs by diffusion, facilitated diffusion, osmosis, and active transport.

Answer 52

Absorption

Question 53

__ are resynthesized to triglycerides and formed into protein-coated spherical masses.

Answer 53

Chylomicrons

Question 54

In order for lipids to be transported in blood and utilized by body cells, the lipids must be combined with protein transporters called __.

Answer 54

Lipoproteins

Question 55

The large intestine (colon) extends from the ileocecal sphincter to the anus. It's subdivisions include:

Answer 55

Cecum, colon, rectum, and anal canal

Question 56

The colon is divided into the following 4 area:

Answer 56

Ascending, transverse, descending, and sigmoid.

Question 57

The muscularis contains specialized portions of longitudinal muscles called __ __.

Answer 57

Taeniae coli

Question 58

__ is the elimination of feces from the rectum.

Answer 58

Defecation