Small and Large Intestine

Question 1

Name the three regions of the small intestine

Answer 1

Duodenum, jejunum, and ileum

Question 2

Structures to increase surface area of the intestine

Answer 2

Plicae circulares, villi, microvilli

Question 3

What are plicae circulares/valves of Kerckring?

Answer 3

Permanent spiral folds of the mucosa and submucosa in the distal duodenum, jej., and proximal ile.

Question 4

What are intestinal villi?

Answer 4

Finger-like projections of mucosa

Question 5

What are the Crypts of Lieberkuhn?

Answer 5

Simple tubular glands extending from approximately the middle of the vilus to the epithelium.

Question 6

What cells reside in the crypts of Lieberkuhn?

Answer 6

Goblet cells, columnar cells, enteroendocrine cells, regenerative cells, paneth cells

Question 7

The microvillus core contains…

Answer 7

actin filaments linked with fimbrin and villin. Actin is anchored with myosin I and calmodulin.

Question 8

Motility of the small intestine is controlled by the __________. More speficially….

Answer 8

Autonomic Nervous System. Meissner’s Plexus and Auerbach’s myenteric plexus.

Question 9

The intestine is lined with ________ epithelium

Answer 9

Simple Columnar

Question 10

Cells in the intestinal epithelium include….

Answer 10

Goblet, Absorptive, Paneth, Antigen Processing, Enteroendocrine

Question 11

Goblet cells produce _______, which after release is converted to ______.

Answer 11

Mucinogen. Mucous.

Question 12

Apical surfaces of enterocytes are covered with…

Answer 12

microvilli covered with glycocalyx

Question 13

Cells are bound by..

Answer 13

zonulae occludens, zonula adherens, and lateral plications

Question 14

Cells divide in the what part of the intestine?

Answer 14

Crypts (before migrating up and being sloughed off at the villus.

Question 15

What enzymes break down carbohydrates? Where?

Answer 15

Lactase, Maltase, and Sucrase in the brush border membrane.

Question 16

What enzymes break down proteins?

Answer 16

Initially - pepsin, trypsin and chymotrypsin. Enterokinase and aminopeptidase in microvilli. Cytoplasmic peptidase later.

Question 17

What breaks down fatty acids?

Answer 17

Pancreatic lipase and bile salts (to make micelles)

Question 18

Micelles are bound to ____ inside the microvilli

Answer 18

Fatty acid binding protein

Question 19

Triglycerides are formed in the

Answer 19

Smooth Endoplasmic Reticulum

Question 20

Where in the cell are chylomicrons formed?

Answer 20

Golgi

Question 21

Enteroendocrine cells of the intestine secrete…

Answer 21

Gastrin, Cholecystokinin, and Gastric Inhibitory Peptide

Question 22

What is the function of M cells?

Answer 22

Antigen uptake/processing/transport (with intraepithelial pocket of B cells)

Question 23

________ cells may extend out processes across the basal lamina near lymphoid follicular epithelium in Peyer’s Patches.

Answer 23

Dendritic

Question 24

Paneth cells contain…

Answer 24

Large eosinophilic apical secretory granules

Question 25

Where are Paneth cells typically located

Answer 25

Bottom of the crypts of Lieberkuhn

Question 26

What do Paneth cells secrete?

Answer 26

Lysozyme (to cleave bacterial cell walls) and defensins (in response to antigens to protect the regenerative cells) and TNF-alpha

Question 27

Where are intestinal regenerative cells located?

Answer 27

Bottom of the crypts.

Question 28

Lacteals are components of the _______

Answer 28

Lymphatic System

Question 29

Brunner's glands are located where?

Answer 29

Submucosa of duodenum

Question 30

What do Brunner's Glands secrete?

Answer 30

Alkaline secretions of glycoproteins, GIP to protect intestine from high acid

Question 31

Gastric Inhibitory Peptide does what?

Answer 31

Enhances epithelial cell division and inhibits HCl production.

Question 32

Aggregate lymphoid nodules are located where?

Answer 32

Ileum

Question 33

Function of the colon?

Answer 33

Absorption of water and electrolytes

Question 34

In the colon you will no longer see the presence of _____

Answer 34

villi, paneth cells, glands

Question 35

The colon has ______- epithelium

Answer 35

simple columnar

Question 36

Outer layer of the muscularis externa forms three longitudinal muscles named...

Answer 36

the teniae coli

Question 37

Name of sacculations of the colon wall

Answer 37

Haustra coli

Question 38

What plexus lives between the muscle layers of the colon?

Answer 38

Auerbach's Plexus

Question 39

Function of appendix?

Answer 39

Somehow involved with preventing intestinal carcinoma. Also reservoir of gut bacteria after diarrhea.

Question 40

The appendix has ______ epithelium

Answer 40

simple columnar

Question 41

Appendix has what cells present

Answer 41

goblet, columnar, regenerative, paneth, and enteroendocrine

Question 42

Crypts of Lieberkuhn are ______ in the colon than the rectume

Answer 42

Fewer and Deeper

Question 43

Longitudinal folds of anal mucosa are called

Answer 43

anal columns

Question 44

Anal epithelium is....

Answer 44

Simple columnar --> simple/stratified cuboidal/columnar --> nonkeratinized strat squamous --> keritinized stratified squamous

Question 45

Gastritis is...

Answer 45

Gastric mucosal inflammation

Question 46

Malabsorption diseases can lead to....

Answer 46

malnutrition/wasting diseases

Question 47

Gluten enteropathy is....

Answer 47

destructive effects of some glutens on the intestinal villi.

Question 48

Steatorrhea is....

Answer 48

stools with high fat/ fat malabsorption

Question 49

Vit K deficiency can cause....

Answer 49

clotting deficiency

Question 50

Vit B12 deficiency can cause...

Answer 50

Pernicious Anemia

Question 51

Colorectal cancer typically arises from...

Answer 51

Adenomatous polyps

Question 52

Colorectal cancer is treated by...

Answer 52

Colon resection

Question 53

Appendicitis symptoms include...

Answer 53

Pain/discomfort in the lower right abdomen, fever, nausea, and elevated white blood cell. Eventually peritonitis, endotoxic shock, and death if ruptures.

Question 54

Hemorrhoids cause...because of...

Answer 54

rectal bleeding during defecation. breakage of thin walled vessels of the plexuses above or below the anorectal line

Question 55

Hirschsprung's disease is caused by...

Answer 55

mutations of 1 of 4 genes (endothelin B, endothelin 3, RET) that prevent neural crest cells from migrating/differentiating into neurons of the enteric nervous system.