11 Digestive System III-- Small and Large Intestines

Question 1

Where are plicae circulares most pronounced? what are they?

Answer 1

jejunum- permanent semicircular fold of mucosa and SUBMUCOSA

Question 2

What are the functions of plicae circulares?

Answer 2

3 fold increase in surface area

slow chyme passage

Question 3

What is the core of villi in small intestines?

Answer 3

lamina propria

Question 4

What is the function of villi in the intestines?

Answer 4

10 fold increase in surface area

Question 5

What is found within the lamina propria of a villus?

Answer 5

vein, artery and lacteal

Question 6

What is the function microvilli?

Answer 6

20 fold increase of surface area

Question 7

What is the epithelial classification in the small intestine?

Answer 7

simple columnar with microvilli

Question 8

What is a single cell exocrine gland that protects walls from acidity of chyme and lubricates so contents can flow?

Answer 8

goblet cells—more numerous as you go

Question 9

What are simple tubular infoldings of the epithelium that extend into the lamina propria?

Answer 9

crypts of lieberkuhn

Question 10

What transports chylomicrons from the villi to the thoracic duct?

Answer 10

lacteal—>lymphatics—>thoracic duct—>left subclavian

Question 11

What are the large glands in the submucosa of the duodenum?

Answer 11

brunners

Question 12

Does the small intestine have a serosa? exception?

Answer 12

yes except for retroperitoneal portion of duodenum

Question 13

T-F the crypts of lieberkuhn are deep at first and progressively get shorter?

Answer 13

false–opposite is true

Question 14

What 5 cells can we find in crypts?

Answer 14

enterocytes
goblet
stem (4-6 just above base)
paneth cells
enteroendocrine

Question 15

What do paneth cells secrete?

Answer 15

lysozyme (destroys bacterial peptidoglycan- gram+) and alpha-defensin (destroys bacterial lipid component - gram-)

Question 16

What are the 3 different types of enteroendocrine cells found in the small intestine?

Answer 16

S-cell
I-cell
enterochromaffin cells

Question 17

What cell is only in the crypts of the duodenum, release secretin in response to low pH? what effect does this have

Answer 17

S cell– [secretin targets parietal cells to secrete less acid, and centroacinar cells to increase alkaline secretion]

Question 18

What cell is in the crypts of duodenum and jejunum and release cholecystokinin? what triggers release?

Answer 18

I cell—fat and protein rich chyme triggers

Question 19

What does cholecystokinin do?

Answer 19

targets pancreatic acinar cells to increase secretion of trypsinogen, also smooth muscle of gallbladder to contract and push bile out

Question 20

What cells are located in the crypts throughout the intestine and release serotonin in response to food? what does this promote?

Answer 20

enterochromaffin cells– peristalsis

Question 21

What do brunners glands release?

Answer 21

alkaline solution 8.1-9.3

Question 22

T-F–the jejunum has both brunners glands and peyers?

Answer 22

False—neither

Question 23

What does the ileum have that distinguishes it from the rest of the intestines?

Answer 23

M cells and peyers patches

Question 24

What is the function of an M cell?

Answer 24

entry of antigens and transportation to the peyers patch for immune responses

Question 25

The large intestines are flat in their cur face but have many holes called what? what do they secrete?

Answer 25

crypts of lieberkuhn and they secrete mucous

Question 26

T-F—there are paneth cells in the large intestine crypts of lieberkuhn?

Answer 26

False

Question 27

What is found and fills the space between crypts in the large intestine?

Answer 27

lamina propria with arteries and veins, and LYMPH NODE MODULES

Question 28

What is different about the outer longitudinal muscle of the large intestine?

Answer 28

form taeniae coli—three bands —>form haustra for compaction

Question 29

Does all of the large intestine have serosa?

Answer 29

not the portion retroperitoneal

Question 30

Does the appendix have teniae coli?

Answer 30

no

Question 31

Are there more or less crypts in the appendix?

Answer 31

fewer

Question 32

Does the appendix have a poorly defined or strongly defined muscular is mucosa?

Answer 32

poorly defined

Question 33

What are very prominent in the lamina propria and submucosa in the appendix?

Answer 33

lymphoid nodules all around, look like peyers but they are not called that