Stomach

Question 1

Functions of the stomach (3)

Answer 1

1. continue digestion of carbohydrates
2. storage primary function
3. some nutrient breakdown (primarily chemical, little physical)

Question 2

What are gastric pits?

Answer 2

tiny depressions in the stomach’s surface; 1 pit leads to more than one gland

Question 3

What are the four luminal wall structures of the stomach?

Answer 3

2. mucosa, submucosa, muscularis externa, and serosa

Question 4

Stomach - Mucosa

1. Surface epithelium: ___, cells (2), What is the function of surface mucous cells
2. LP: ___ CT present in ___ amounts b/w glands
3. MM: ___ muscle layer that is often arranged in # layers, list them

Answer 4

1. simple columnar, surface mucous (surface lining) and regenerative cells (bases of pits), produce thick visible mucus and secrete bicarbonate ions
2. loose vascular, small
3. smooth, 3, inner circular-outer longitudinal-outermost circular/oblique

Question 5

Stomach - Submucosa

1. highly ___
2. location of ___, whose function is to ?
3. ___ is next to inner circular layer of muscle, function?

Answer 5

1. vascular
2. AVA (arteriovenous anastomosis, to shut down activity and secretion FAST
3. submucosal (Meissner’s) Plexus, to influence the mucosa and secretion, blood flow, any limited muscle contractions

Question 6

Stomach - Muscularis Externa

1. # muscle layers possible, especially b/w (2), all ___ muscle
2. list the three layers
3. ___ pattern at other locations
4. ___ b/w circular and longitudinal layers of muscle, function?

Answer 6

1. 3, cardiac region and greater curvature, smooth
2. innermost oblique (sometimes), middle circular (well developed), outer longitudinal
3. normal
4. myenteric (Auerbach’s) plexus, to stimulate the muscularis externa

Question 7

Stomach - Serosa

1. covers how much?

Answer 7

1. all

Question 8

1. What is the surface epithelium of the stomach?

2. what is the layer covering (opposite the lumen) the stomach?

Answer 8

1. simple columnar

2. serosa

Question 9

Gastric histology is based on what three regions of the stomach?

Answer 9

1. cardiac
2. gastric (fundus and body)
3. pyloric

Question 10

Cardiac Region -

1. ___ pits which lead to ___ with a ____
2. Cells: primarily ___, some ___, and a few (2), NO ___ cells
3. ___ region, and obtain much ___

Answer 10

1. shorter, cardiac glands, coiled base
2. surface mucous, neck mucous, DNES and parietal, chief cells
3. smallest, mucus

Question 11

Gastric Region -

1. Gastric glands extends from ___ to ___
2. What are the three regions in a gastric gland (___ gland)

Answer 11

1. gastric pit to MM

2. surface mucous, Isthmus, Neck, (Zymogenic)

Question 12

Gastric Gland - Isthmus

1. Surface Mucous: live ___, produce ___ that traps ___, Function
2. DNES cells: AKA ___ cells, how many?, List the three types of DNES cells in the stomach

Answer 12

1. 3-5 days, thick visible mucus, bicarbonate ions, to protect mucosa from auto-digestion and the rougher components of chime
2. enteroendocrine, few, Type D, EC, and G

Question 13

Types of DNES Cells -

1. Type D: produces ___, function
2. Type EC: produces (2), function
3. Type G: produces ___, function

Answer 13

1. somatostatin, inhibits release of hormones by nearby DNES cells and HCL release
2. serotonin and substance P, increases gut motility
3. gastrin, stimulates HCL and pepsinogen secretion, gastric motility, and regenerative cells in body of stomach

Question 14

Gastric Gland - Neck

1. What are the four types of cells here?
2. Neck mucous cells: live ___, produce ____, function
3. Regenerative Cells: replace ___
4. Parietal ___ cells: live ___, describe, Produce (2)

Answer 14

1. neck mucous cells, regenerative cells, parietal cells, and DNES cells
2. 6 days, soluble/slightly acidic mucus, to lubricate gastric contents
3. all cell types
4. oxyntic, 150-200 days, odd columnar cells with intracellular canaliculi, very strong HCL (made at 0.8 pH and buffered immediately to 1-2 pH) and Gastric intrinsic factor (function: necessary for vit B12 absorption

Question 15

1. Chronic Gastritis can lead to ___
2. Low number of ___ cells can lead to low amounts of ____
3. This will decrease ___ absorption which is necessary for ____

Answer 15

1. pernicious anemia
2. parietal, intrinsic factor
3. vit B12, RBC maturation

Question 16

Gastric Gland - Base

1. has what three types of cells
2. chief (___) cells: live ___, produce (2) whose jobs are?
3. Parietal cells: amount
4. DNES cells: live ___, amount

Answer 16

1. chief, parietal, DNES
2. zymogenic, 60-90 days, primarily pepsinogen (break down proteins) and some gastric lipase (break down fats)
3. some
4. 60-90 days, few

Question 17

Pyloric Region -

1. ___ pits, explain
2. cells are primarily (3), some ___ cells that also produce some ___

Answer 17

1. deeper, very twisted and branched pyloric glands (shorter glands)
2. surface mucus, DNES and parietal, neck mucous, lysozyme

Question 18

Pyloric Region -

1. Pyloric Sphincter: define
2. What are the two characteristics of an anatomical sphincter?

Answer 18

1. the anatomical sphincter between the pylorus of the stomach and the duodenum
2. -well developed inner circular layer of muscle in the ME, - inner circular layer in ME can be independently controlled

Question 19

Which stomach cells produce…

1. intrinsic factor
2. thick visible mucus
3. pepsinogen
4. HCL
5. a more soluble slightly acidic mucus

Answer 19

1. parietal
2. surface mucous
3. chief
4. parietal
5. neck mucus

Question 20

Which stomach cells produce…

1. gastrin
2. gastric lipase

Answer 20

1. DNES type G cell

2. Chief

Question 21

1. Which layer of muscle within the ME is not always present?
2. Name surface epithelium of stomach

Answer 21

1. oblique

2. simple columnar