Ch. 17 Digestive System II: Esophagus & GI Tract (FINAL)

Question 1

The portion of the {…} canal that extends from the proximal part of the esophagus to the distal part of the anal canal is a hollow tube of varying diameter.

Answer 1

Alimentary

Question 2

List the 4 layers of the alimentary canal.

Answer 2

1) Mucosa
2) Submucosa
3) Muscularis externa
4) Serosa

Question 3

Alimentary canal layer consisting of a lining epithelium, an underlying connective tissue called the lamina propria, and the muscularis mucosae, composed of smooth muscle.

Answer 3

What is the mucosa?

Question 4

Alimentary canal layer consisting of dense irregular connective tissue.

Answer 4

What is the submucosa?

Question 5

Alimentary canal layer consisting, in most parts, of 2 layers of smooth muscle.

Answer 5

What is the muscularis externa/

Question 6

Alimentary canal layer consisting of a serous membrane consisting of a simple squamous epithelium, the mesothelium, and a small amount of underlying connective tissue.

Answer 6

What is the serosa?

Question 7

An {…} consisting only of connective tissue is found where the wall of the tube is directly attached or fixed to adjoining structures (i.e., body wall and certain retroperitoneal organs).

Answer 7

Adventitia

Question 8

List the 3 principle functions of the mucosa.

Answer 8

1) Protection
2) Absorption
3) Secretion

Question 9

Structural specializations of the mucosa and submucosa that are circumferentially oriented submucosal folds present along most of the length of the small intestine.

Answer 9

What are plicae circulares?

Question 10

These specializations are mucosal projections that cover the entire surface of the small intestine, the principal site of absorption of the products of digestion.

Answer 10

What are villi?

Question 11

These specializations are tightly packed, microscopic projections of the apical surface of intestinal absorptive cells. They further increase the surface available for absorption.

Answer 11

What are microvilli?

Question 12

In addition, the {…} consists of glycoproteins that project from the apical plasma membrane of epithelial absorptive cells.

Answer 12

Glycocalyx

Question 13

These glands extend into the lamina propria.

Answer 13

What are mucosal glands?

Question 14

These secretory structures are glands that deliver their secretions either directly to the lumen of mucosal glands or via ducts that pass through the mucosa to the luminal surface.

Answer 14

What are submucosal glands?

Question 15

These secretory structures are glands hat lie outside the digestive tract and deliver their secretions via ducts that pass through the wall of the intestine to enter the lumen.

Answer 15

What are extramural glands?

Question 16

Extramural glands deliver their secretions into the {…}, the first part of the small intestine.

Answer 16

Duodenum

Question 17

The diffuse lymphatic tissue and the lymphatic nodules are referred to as {…} (GALT).

Answer 17

Gut-associated lymphatic tissue

Question 18

In the distal small intestine, the {…}, extensive aggregates of nodules, called {…} patches, occupy much of the lamina propria and submucosa.

Answer 18

1) Ileum
2) Peyer

Question 19

The deepest portion of the mucosa consisting of smooth muscle cells arranged in an inner circular and outer longitudinal layer.

Answer 19

What is the muscularis mucosae?

Question 20

The {…} contains the larger blood vessels that send branches to the mucosa, muscularis externa, and serosa.

Answer 20

Submucosa

Question 21

In the submucosa, the nerve cell bodies of parasympathetic ganglia and their postganglionic nerve fibers represent the {…} nervous system, the third division of the autonomic nervous system.

Answer 21

Enteric

Question 22

In the submucosa, the network of unmyelinated nerve fibers and ganglion cells constitute this plexus.

Answer 22

What is the submucosal (Meissner) plexus?

Question 23

The slow, rhythmic contraction of the muscle layers of the muscularis externa under the control of the enteric nervous system produces {…} (i.e., waves of contraction).

Answer 23

Peristalsis

Question 24

Finally, in the large intestine, part of the longitudinal smooth muscle layer is thickened to form three distinct, equally spaced longitudinal bands called {…} coli.

Answer 24

Teniae

Question 25

List the 5 circular muscle layers of the GI tract from superior to inferior.

Answer 25

1) Pharyngoesophageal sphincter 2) Inferior esophageal sphincter 3) Pyloric sphincter 4) Ileocecal valve 5) Internal anal sphincter

Question 26

The serosa is a serous membrane consisting of a layer of simple squamous epithelium, called the {...}, and a small amount of underlying connective tissue.

Answer 26

Mesothelium

Question 27

As such, the serosa is continuous with both the {...} and lining of the abdominal cavity.

Answer 27

Mesentery

Question 28

This sphincter controls the release of chyme, the partially digested contents of the stomach, into the duodenum.

Answer 28

What is the pyloric sphincter?