Lecture 27: Midgut and Hindgut Flashcards
the jejunum and ileum are located in the ventral edge of the _____
great mesentery
jejunal arteries supply what
distal duodenum and jejunum
the caudal pancreaticoduodenal artery supplies what
right pancreatic lobe and the middle of the duodenum
what does the ileocolic artery supply
ascending colon
middle colic artery supplies what
first 2/3 of transverse colon
what are the 2 branches of the ileocolic artery
cecal + right colic
What is digestion
breakdown of complex nutrients into simple molecules
what is absorption
transporting molecules across intestinal epithelium
what things does the colon absorb
water
vitamins
electrolytes
anatomical transition from foregut to midgut
duodenum
what are plica circulares in the duodenum
non-distendable (don’t flatten) folds covered w/ intestinal villi
act to increase SA of the proximal small intensine
the surface of each circular fold/plica circularis is covered by projections called?
intestinal villi
each villus of the circular fold is covered with what type of cells
goblet cells &
simple columnar epithelial with microvilli for absorption
what is a lacteal
specialized lymphatic capillary network found within in villus
components of the enterocyte cells
Absorptive function:
tall microvilli
tight junctions
lateral enfoldings
Digestive function:
glycocalyx enzymes
glycoproteins w/ mucous
where can Brunner’s Glands be found and what do they do?
in the proximal part of the duodenum, closest to pylorus
they have specialized mucous secreting glands to protect the duodenal lining from acidic chyme
what do Brunner’s glands secrete
peptide hormone UROGASTRONE that inhibits HCl secretion
What do fenestrated capillaries transport
proteins, carbs
what do Lymphathic capillaries (Lacteals) transport
dietary fats
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
muscularis mucosa
glands found only in the duodenum that secrete alkaline fluid to raise the pH of incoming chyme
Brunner’s glands
what type of animals lack direct connection bw their cecum and ileum
carnivorans
the cecum communicates w/ the ascending colon through the _________ that is adjacent to the ileal orifice
Cecocolic orifice
evaginated submucosa covered with mucosa found in the jejunum and ileum that increase SA for absorption
cannot flatten
plicae circulares
where does the ileum and small intestine end
ileocolic junction
