Esophagus and Stomach

Question 1

The digestive system includes…

Answer 1

Oral Cavity and Alimentary Canal (Esophagus, Stomach, Small and Large Intestine, Extrinsic Glands)

Question 2

Layers in the digestive tract?

Answer 2

Mucosa, Submucosa, Muscularis Externa, Serosa

Question 3

The esophagus is lined with what kind of cells?

Answer 3

Nonkeratinized Stratified Squamous

Question 4

Glands in the lamina propria of the esophagus? They secrete what?

Answer 4

Esophageal Cardiac Glands – Mucus

Question 5

Name of glands of the submucosa of the esophagus? They secrete what?

Answer 5

Esophageal Glands Proper – Mucus with a little bit of lysozyme secreting serous cells

Question 6

Muscle types of the esophagus?

Answer 6

Striated in top 1/3. Smooth in bottom 1/3. Both in the middle.

Question 7

Alternative name of recently swallowed food

Answer 7

Bolus

Question 8

Name the two sphincters of the esophagus and their location.

Answer 8

Pharyngoesophageal (upper) and Gastroesophageal (lower) sphincters make sure bolus moves in only one direction.

Question 9

Purpose of Pharyngeoesophageal Sphincter?

Answer 9

Initiates Swallowing

Question 10

Purpose of gastroesophageal sphincter?

Answer 10

Prevents acid reflux from the stomach.

Question 11

Persistent acid reflux can lead to…

Answer 11

Gastroesophageal reflux disease.

Question 12

What is Barrett’s esophagus?

Answer 12

Abnormal growth of simple columnar intestinal cells in the lower esophagus. Can be injured by stomach acid and increase cancer risk.

Question 13

What is a hiatal hernia?

Answer 13

Esophageal hiatus does not close entirely resulting in portions of the stomach moving into the thoracic cavity.

Question 14

Why have a stomach anyway?

Answer 14

Acidifies and converts food into chyme. Produces enzymes and hormones.

Question 15

Name of longitudinal folds of the mucosa and submucosa?

Answer 15

Rugae

Question 16

Describe the glands of the cardia region.

Answer 16

Tubular with a coiled end. Make mucus.

Question 17

Describe the glands of the fundus.

Answer 17

Simple tubular glands. Shallow gastric gland pits.

Question 18

Describe the glands of the pylorus.

Answer 18

Deep gastric pits with branched glands. Primarily mucus with occasional parietal cells. Also G cells around.

Question 19

The lining of the stomach is comprised of…

Answer 19

mucus producing simple columnar cells

Question 20

Describe the muscle layers of the stomach.

Answer 20

Incomplete inner oblique, thick middle circular, outer longitudinal

Question 21

Meissner’s plexus can be found in which layer?

Answer 21

Gastric Submucosa.

Question 22

What covers the outer surface of the stomach?

Answer 22

Gastric serosa.

Question 23

What chyme characteristics will influence stomach emptying rate?

Answer 23

Viscosity, pH, lipid content, osmolarity, caloric density

Question 24

What are the components of a gastric gland?

Answer 24

Simple tubular glands with an isthmus connecting the gland to the bast and neck of a gastric pit.

Question 25

Types of cells in a gastric pit?

Answer 25

Parietal, chief, mucous neck, enteroendocrine, regenerative

Question 26

Surface cells secrete what?

Answer 26

Thick mucous with a high bicarbonate content.

Question 27

Describe mucous neck cell structure.

Answer 27

Short microvilli, apical mucous granules, priminent golgi

Question 28

Pariatal cells stain what color?

Answer 28

Red/pink with H&E

Question 29

What purpose to parietal cells serve?

Answer 29

Secrete HCl and Gastric Intrinsic Factor

Question 30

What does gastric intrinsic factor do?

Answer 30

aids Vitamin B12 absorption in SI

Question 31

Describe the cellular structure of parietal cells.

Answer 31

Intracellular tubovesicular system, many mitochondria, secretory intracellular cannaliculi.

Question 32

What can increase the effects of acetylcholine and gastrin on parietal activity?

Answer 32

Histamine activating histamine H2 receptor

Question 33

What glands in the digestive tract produce histamine?

Answer 33

Enterochromaffin-like cells in lamina propria around gastric glands

Question 34

Two ways to drug acid secretion?

Answer 34

1. Inhibit histamine-dependent acid secretion (Cimetidine) | 2. Bind to the H+, K+ dependent ATPase to inactivate acid secretion (Omeprazole)

Question 35

Parietal cells release bicarbonate, which can cause...

Answer 35

variations in blood and mucous pH

Question 36

How do chief cells stain?

Answer 36

Blue with H&E

Question 37

What do chief cells secrete?

Answer 37

Pepsinogen, Rennin, and Lipase precursors

Question 38

Describe the cellular structure of a chief cell

Answer 38

Abundant basally located RER, Supranuclear golgi, apical secretory granules

Question 39

How many hormones might a given enteroendocrine cell secrete?

Answer 39

One

Question 40

Other names for enteroendocrine cells?

Answer 40

DNES (diffuse neuroendocrine cells), APUD (amine precursor uptake and decarboxylation cells)

Question 41

pH at which pepsin is activated?

Answer 41

2.0

Question 42

Where is secretin from? What does it do?

Answer 42

Secretin is from cells of the duodenum. Stimulates pancreatic HCO3 and pepsinogen release.

Question 43

Where is gastrin from? What does it do?

Answer 43

G cells in the duodenum and the pylorus. Stimulates HCl secretion.

Question 44

Where is somatostatin from? What does it do?

Answer 44

D cells of the pylorus and duodenum. Inhibits Gastrin.

Question 45

Where is Gastric Inhibitory Peptide from? What does it do?

Answer 45

Duodenum and Jejunum. Inhibits HCl secretion and promotes Insulin release.

Question 46

Where is Cholecystekinin from? What does it do?

Answer 46

From Duodenum and Jejunum. Stimulates gall bladder contraction when a lot of fat is in the SI.

Question 47

Where is Motilin from? What does it do?

Answer 47

Released cyclically during fasting from cells of the upper GI.

Question 48

What is gastritis?

Answer 48

Gastric mucosal inflammation. May be superficial or entire length.

Question 49

What is Zolinger-Ellison syndrome?

Answer 49

Gastrin-secreting tumors causing high acid levels, ulcers, diarrhea.

Question 50

What are gastric/peptic ulcers?

Answer 50

Areas of the mucosa destroyed by gastric secretions commonly in cardiac, pyloric regions or duodenum.

Question 51

Causes of ulcers?

Answer 51

Too much HCl secretion, nervous irritation, H. pylori infection, NSAIDS

Question 52

What are the phases of an H. pylori infection?

Answer 52

Active Phase -- increasing the gastric pH by ammonia production Stationary Phase -- Attach to fucose receptors on the mucus cells. Release proteases that kill surface cells. Colonization Phase -- Bacteria detach and reproduce in mucus blanket.