Small Intestine

Question 1

what is included in the small intestine?

Answer 1

duodenum
jejunum
ileum

Question 2

what are villi?

Answer 2

finger like projections on epithelium

Question 3

what are crypts of Lieberkuhn?

Answer 3

crypts between adjacent villi

Question 4

what are enterocytes?

Answer 4

the principle absorptive cell
most numerous cell in small intetsine
tall columnar cells with a brush border

Question 5

what domgobelt cells do?

Answer 5

produce mucin to protect epithelium and lubricste passageway for material

Question 6

what are panted cells?

Answer 6

cells found at the base of Lieberkuhn crypts
protective function - regulate bacterial flora

Question 7

what are enteroendocrine cells?

Answer 7

cells that produce hormones
contribute to control of secretion and motility

Question 8

what are stem cells?

Answer 8

cells that divide to replenish epithelium
found at bottom of crypts of Lieberkun

Question 9

where does the duodenum start and end?

Answer 9

starts at the pylors
ends at duodenojejunal junction

Question 10

what does the duodenum receive?

Answer 10

chyme from the stomach

Question 11

what shape is the duodenum?

Answer 11

C

Question 12

how many parts is the duodenum split into?

Answer 12

4
superior
descending
horizontal
ascenidng

Question 13

what vertebral level is the superior duodenum?

Answer 13

L1

Question 14

what vertebral level is the descending duodenum?

Answer 14

L1-3

Question 15

what vertebral level is the horizontal duodenum?

Answer 15

L3

Question 16

what vertebral level is the ascending duodenum?

Answer 16

L3-2

Question 17

what part pf the duodenum is intraperitoneal?

Answer 17

superior duodenumw

Question 18

what parts of the duodenum are retroperitoneal?

Answer 18

descending
horizontal
ascending

Question 19

where is the descending duodenum?

Answer 19

it curves inferiorly around the head of the pancreas
it is marked by major duodenal papilla where bile and pancreatic secretions enter from the ampulla of Vater

Question 20

where is the horizontal duodenum?

Answer 20

travels laterally to the left, crossing over the inferior vena cava and aorta
inferior to the pancreas
posterior to the superior mesenteric artery and vein

Question 21

where is the ascending duodenum?

Answer 21

ascends and curves anteriorly to join the jejunum at a sharp turn - duodenojejunal flexure

Question 22

what does the duodenum secret?

Answer 22

peptide hormones - i.e gastrin, CCK

Question 23

where does pain from a duodenal ulcer tend to present?

Answer 23

epigastric region

Question 24

where are Brunner’s glands?

Answer 24

in the submucosa of the duodenum
- only glands in digestive tract below the oesophagus

Question 25

what do Brunner's glands do?

Answer 25

when stimulated by chyme they produce a thin alkaline mucous to neutralise the chyme

Question 26

what part of the duodenum does the superior gastroduodenal artery supply?

Answer 26

the foregut - the bit proximal to the major duodenal papilla

Question 27

what part of the duodenum does the inferior pacreaticoduodenal artery (branch of superior mesenteric artery) supply?

Answer 27

the midgut - the bit distal to the major duodenal papilla

Question 28

where do the veins of the duodenum drain?

Answer 28

they follow the major arteries and drain into the hepatic portal vein

Question 29

is the jejunum and ileum intraperitoneal or retroperitoneal?

Answer 29

retroperitonela

Question 30

how long is the jejunum?

Answer 30

around 3m

Question 31

how long is the ileum?

Answer 31

around 4m

Question 32

where does the jejunum start?

Answer 32

at the duodenaljujunal jucntion around L2

Question 33

where does the ileum end?

Answer 33

ileocaecal junction

Question 34

is there a junction between the jejunum and ileum?

Answer 34

no clear junction macroscopically different

Question 35

what is the mucosa of the jejunum like?

Answer 35

highly folded - plicae circularis

Question 36

what is the mucosa of the ileum like in comparison to the jujunum?

Answer 36

much smoother

Question 37

what is the histology of the jejunum?

Answer 37

tallest villi on permanent circular folds of mucosa (plicae circulars) infrequent lymphoid follicles

Question 38

what is the histology of the ileum?

Answer 38

shorter villi aggregations of lymphoid tissue - Peyer's patches

Question 39

where are Payer's patches found?

Answer 39

in the submucosa of the ileum often extending to the lamina propria

Question 40

what is the arterial blood supply of the jejunum and ileum?

Answer 40

from the superior mesenteric artery via the jejunal and ileal arteries

Question 41

what is the venous drainage of the jejunum and ileum?

Answer 41

jejunal and ileal veins drain into the superior mesenteric vein which drains into the hepatic portal vein