Lecture 27: Midgut and Hindgut

Question 1

the jejunum and ileum are located in the ventral edge of the _____

Answer 1

great mesentery

Question 2

jejunal arteries supply what

Answer 2

distal duodenum and jejunum

Question 3

the caudal pancreaticoduodenal artery supplies what

Answer 3

right pancreatic lobe and the middle of the duodenum

Question 4

what does the ileocolic artery supply

Answer 4

ascending colon

Question 5

middle colic artery supplies what

Answer 5

first 2/3 of transverse colon

Question 6

what are the 2 branches of the ileocolic artery

Answer 6

cecal + right colic

Question 7

What is digestion

Answer 7

breakdown of complex nutrients into simple molecules

Question 8

what is absorption

Answer 8

transporting molecules across intestinal epithelium

Question 9

what things does the colon absorb

Answer 9

water
vitamins
electrolytes

Question 10

anatomical transition from foregut to midgut

Answer 10

duodenum

Question 11

what are plica circulares in the duodenum

Answer 11

non-distendable (don’t flatten) folds covered w/ intestinal villi

act to increase SA of the proximal small intensine

Question 12

the surface of each circular fold/plica circularis is covered by projections called?

Answer 12

intestinal villi

Question 13

each villus of the circular fold is covered with what type of cells

Answer 13

goblet cells &
simple columnar epithelial with microvilli for absorption

Question 14

what is a lacteal

Answer 14

specialized lymphatic capillary network found within in villus

Question 15

components of the enterocyte cells

Answer 15

Absorptive function:
tall microvilli
tight junctions
lateral enfoldings

Digestive function:
glycocalyx enzymes
glycoproteins w/ mucous

Question 16

where can Brunner’s Glands be found and what do they do?

Answer 16

in the proximal part of the duodenum, closest to pylorus

they have specialized mucous secreting glands to protect the duodenal lining from acidic chyme

Question 17

what do Brunner’s glands secrete

Answer 17

peptide hormone UROGASTRONE that inhibits HCl secretion

Question 18

What do fenestrated capillaries transport

Answer 18

proteins, carbs

Question 19

what do Lymphathic capillaries (Lacteals) transport

Answer 19

dietary fats

Question 20

smooth muscle that is organized into inner circular and outer longitudinal layers that during contraction, moves mucosa, forming ridges and valleys that facilitate absorption and secretion

Answer 20

muscularis mucosa

Question 21

glands found only in the duodenum that secrete alkaline fluid to raise the pH of incoming chyme

Answer 21

Brunner’s glands

Question 22

what type of animals lack direct connection bw their cecum and ileum

Answer 22

carnivorans

Question 22

the cecum communicates w/ the ascending colon through the _________ that is adjacent to the ileal orifice

Answer 22

Cecocolic orifice

Question 22

evaginated submucosa covered with mucosa found in the jejunum and ileum that increase SA for absorption

cannot flatten

Answer 22

plicae circulares

Question 23

where does the ileum and small intestine end

Answer 23

ileocolic junction