2A-A&P of the STOMACH

Question 1

What are the 4 main regions of the stomach? (in order of proximal to distal)

Answer 1

Cardia–>Fundus–>Body–>Pylorus(Antrum&Canal)

Question 2

What are the two sphincters of the stomach?

Answer 2

the LES and the Pyloric

Question 3

What are the three layers of the muscularis externa in the stomach? FROM OUTERMOST to Innermost

Answer 3

1.Outermost Longitudinal 2.Middle Circular 3. Innermost Oblique*unique to stomach!

Question 4

Which omentum is on the rostral(head) portion of the stomach?

Answer 4

Lesser Omentum (think space!)

Question 5

Which omentum is on the caudal (tail) part of the stomach?

Answer 5

Greater Omentum

Question 6

What is the name for the layer of alkaline mucus?

Answer 6

Gastric Mucosal Barrier

Question 7

KEY TO DRUG understanding: What molecules play an important role in protecting the stomach mucosa from injury by enhancing mucus production?

Answer 7

PROSTAGLANDINS-Using NSAIDs block prostaglandin production and can cause weakening of the mucosal layer

Question 8

What are the LARGE hills and valleys of the stomach walls?

Answer 8

RUGAE

Question 9

What are the millions of deep channels on the rugae of the stomach wall?

Answer 9

Gastric Pits

Question 10

The mucosal surface of the stomach is a ___________ epithelium.

Answer 10

Simple Columnar

Question 11

What are the specialized cells of the gastric pits?

Answer 11

Gastric Glands

Question 12

What is the average lifespan of a stomach cell?

Answer 12

2-3 Days

Question 13

What are the stem cells of the stomach?

Answer 13

Regenerative Cells-they can turn into any cell

Question 14

HAHA what are the cells that line the surface of the gastric mucosa?

Answer 14

Surface Lining Cells

Question 15

Which cells secrete alkaline mucus?

Answer 15

Mucus Neck Cells

Question 16

Which cells secrete HCl & Intrinsic Factor?

Answer 16

Parietal Cells

Question 17

What are the two main functions of Intrinsic Factor?

Answer 17

Absorption and ErythroPoesis

Question 18

Which cells secrete pepsinogen and Gastric Lipase?

Answer 18

Chief Cells

Question 19

Which cells secrete Gastrin (G cells) & Histamine (ECL cells)?

Answer 19

Endocrine Cells

Question 20

What is another name for a Parietal Cell?

Answer 20

OX-IN-TIC (oxyntic)

Question 21

What is another name for a Chief cell?

Answer 21

ZY-MO-GENIC

Question 22

What is another name for an endocrine cell?

Answer 22

EnteroEndocrine Cell

Question 23

Review from earlier…How much Gastric Juice is produced daily?

Answer 23

2.5L…BOOM

Question 24

The _____ junctions between the cells are also part of the mucosal barrier that protects the gastric epithelium from damage.

Answer 24

Tight

Question 25

What are the four examples of substances that can disrupt the mucus layer?

Answer 25

Ethanol, Bile Salts, NSAIDs, and H. Pylori

Question 26

What hormone and cell stimulates parietal cells to produce IF and HCl?

Answer 26

Gastrin from Endocrine Cells (G cells)

Question 27

How much bolus can the stomach hold?

Answer 27

3-6 L of Crap!

Question 28

What is the creamy,soupy paste produced by the stomach?

Answer 28

Chyme

Question 29

Do the Proton Pumps of a Parietal Cell require ATP?

Answer 29

YES! Pumping H+ against its [Gradient]

Question 30

What is the end result in the blood of HCl production in the stomach? So what can happen to the pH of blood after a meal?

Answer 30

An Alkaline Tide, BiCarb is released into the blood while H+ is released into the stomach (same as blood buffer equation)...pH can Increase after a meal

Question 31

What are the three phases of Gastric Secretion and Motility?

Answer 31

1.Cephalic Phase 2.Gastric Phase 3.Intestinal Phase

Question 32

Which phase is preparatory? Which CN is stimulating the prep?

Answer 32

Cephalic Phase, VAGUS stimulates gastric juice production and therefore more gastrin and gastric juice

Question 33

Which phase begins when food reaches the stomach?

Answer 33

Gastric Phase

Question 34

What is the positive feedback loop caused when the stomach is distended with food?

Answer 34

Gastrin release to stimulate the Parietal cells to release more gastric juices

Question 35

Which hormone increases levels of HCl secretion from parietal cells?

Answer 35

HISTAMINE

Question 36

What converts Pepsinogen to Pepsin?

Answer 36

HCl

Question 37

What are the three hormones that inhibit gastric juice secretion in Intestinal Phase?

Answer 37

1.CCK ("Cole-E-sis-TA-K-eye-NIN") 2. Secretin 3.Gastric Inhibitory Peptide

Question 38

What are the two functions of GIP (Gastric Inhibitory Peptide)?

Answer 38

1.Stop Gastric Juice Production 2.Inhibit Gastric Motility

Question 39

What are the three things that can stimulate H+ production in a Paritetal Cell?

Answer 39

1. Histamine 2.Gastrin 3.Vagus Nerve-Acetylcohline

Question 40

What type of receptor does Histamine work on in Parietal cells?

Answer 40

H2

Question 41

What is the reflex when products of protein digestion and H+ in the duodenum inhibit vagus nerve activity? Which phase?

Answer 41

EnteroGastric Reflex (Intestinal Phase)

Question 42

Is there absorption of nutrients in the stomach?

Answer 42

NOPE