Gross Histology of Alimentary Tract

Question 1

Lamina propria

Answer 1

Loose tissue that contains blood vessel and connective tissue in which surface epithelium of gut sits

Question 2

Muscularis mucosae

Answer 2

the muscle that lies around the lamina propria and surface epithelium

Question 3

3 components of GI mucosa

Answer 3

surface epithelium, lamina propria, muscularis mucosae

Question 4

Layers of vsiceral gut (7)

Answer 4

adventitia or serosal layer, outer longitudinal muscle, inner circular muscle, submucosa, muscularis mucosae, lamina propria, surface epithelium

Question 5

Nerve plexi of visceral gut (2)

Answer 5

submucosal nerve plexus, myenteric plexus (between two muscle layers)

Question 6

3 ways cells stick together

Answer 6

tight junctions, desmosomes, shared cell wall + gap junction

Question 7

Network of sealing protein fibers of transmembrane proteins embedded in plasma membranes of two cells with extracellular domains joining one another directly

Answer 7

tight junction

Question 8

Molecular complexes of cell adhesion proteins and linking proteins that attach the cell surface adhesion proteins to intracellular keratin cytoskeletal filaments

Answer 8

desmosomes

Question 9

Direct connections of cytoplasm of two cells via hydrophilic channels which allow molecules and ions to pass freely between.

Answer 9

gap junctions

Question 10

Is there secretion in the esophagus

Answer 10

A little

Question 11

Is there absorption in the esophagus

Answer 11

No

Question 12

Gastric pits

Answer 12

holes in the rugal folds of stomach that are the conduit of gastric glands

Question 13

_____ acid is produced by _____ cells in the stomach.

Answer 13

hypochloric acid produced by parietal cells

Question 14

Parietal cells are stimulated to produce acid by ____ and _____ in the stomach

Answer 14

histamine and gastrin

Question 15

Gastrin is secreted by _____ cells into the blood stream.

Answer 15

stomach antral neuroendocrine cells

Question 16

____ acts directly on parietal cells and stimulates enterochromaffin like cells in the corpus of the stomach.

Answer 16

Gastrin

Question 17

Enterochromaffin like cells in the stomach excrete ____

Answer 17

histamine

Question 18

Another name for mucosa of the fundus

Answer 18

oxyntic mucosa

Question 19

Are there inflammatory cells in the normal lamina propria?

Answer 19

No

Question 20

Chief cells in the stomach produce ____

Answer 20

pepsinogen

Question 21

Gastric pits are lined by _____ epithelium

Answer 21

foveolar

Question 22

Defining feature of small intestine epithelium

Answer 22

Fingerform villi with epithelium outside and crypts with epithelium inside

Question 23

4 mechanisms of absorption

Answer 23

passive diffusion, facilitated passive diffusion, active transport, pinocytosis

Question 24

_____ in lamina propria absorb dietary lipids into the lymphatic system from the small intestine.

Answer 24

Lymph vessels/lacteals

Question 25

_____ cells in the small intestine provide phagocytosis and intracellular digestion of intestinal microorganisms.

Answer 25

Paneth

Question 26

_____ glands in the duodenum produce a mucus-rich alkaline secretion containing bicarbonate that has 2 functions.

Answer 26

Brunner glands in the duodenal submucosa

1. protection from gastric acid
2. alcalization to allow digestive enzymes to work

Question 27

Molecules absorbed in colon

Answer 27

water, sodium, chloride

Question 28

Molecules secreted in colon

Answer 28

bicarbonate, mucus

Question 29

____ cells secrete mucus in response to tactile stimuli from luminal contents, lubricant that protects the epithelium, and binds ingested material to form feces in the colon.

Answer 29

goblet

Question 30

Are there villi in the colon?

Answer 30

No –> only crypts

Question 31

Are inflammatory cells in the lamina propria of the colon normal?

Answer 31

Yes- -> can have none all the way up to a lot

Question 32

Lymphoid tissue associated with mucosa is called ____

Answer 32

mucosa associated lymphoid tissue (MALT) –> very protective from all the goop in the GI tract

Question 33

In MALT, antigenic material is exposed to ___ cells which are associated in antigen transport and antigen presentation in the lymphoid tissue.

Answer 33

M cells

Question 34

Lymph follicles that become large and frequent in the bowel are called _____

Answer 34

peyer patches

Question 35

Stimulation of B lymphocytes leads to the production of Ig ___ and ___ in the peyer patches, preventing adherence of bacteria and viruses to the epithelium.

Answer 35

IgA and IgM

Question 36

The major effector mechanism of MALT

Answer 36

direct secretion of IgA onto mucosal epithelia

Question 37

The activity of ______ in follicle-associated epithelium of intestine is the key to MALT immunity.

Answer 37

germinal centers

Question 38

Is there lymph tissue in the esophagus

Answer 38

Not really –> rarely have follicles in epithelium but have accumulation of intraepithelial lymphocytes in reflux disease

Question 39

Are there lymphoid tissues in the stomach

Answer 39

Not usually –> accumulation of lymphoid cells can occur in chronic gastritis

Question 40

Normal location of lymphoid tissue in small intestine.

Answer 40

lamina propria, villi, in between crypts; large aggregates in peyer’s patches in ilium // in celiac disease, T cells accumulate in surface epithelium

Question 41

Normal location of lymphoid tissue in colon..

Answer 41

lamina propria with mucosal and submucosal follicles // in lymphocytic colitis, T cells accumulate in surface epithelium