Chapter 23: Digestive System Flashcards
Peritoneum
parietal and visceral; simple squamous on top of CT basement membrane
Mesenteries
double layered extesnions of the peritoneum; provide routes for blood vessels lympahtic and nerves; hold organs in place; store fat
Greater Omentum
extends from stomach and drapes over small intestines
Retroperitoneal
organs that are outside the peritoneum; some of pancreas; kidney and part of large intestine and bladder; these organs are covered by adventitia
Peritonitis
inflammation of perotinium
Four Layers of the GI Tract
inner is mucosa (epithelium, lamina propria, and muscularis mucosae); next layer is submucosa (blood vessels and glands); next layer muscularis externa (mostly responsible for peristalsis, circular layer and longitudinal layer); outer layer is serosa (CT, epithelium) or adventitia
Splanchnic Circulation
feeds/drains digestive organs
Arterial Supply..
consists of celiac trunk which serves stomach, spleen and pancreas; and superior/inferior mesenteric arteries serve small and large intestine
Hepatic Portal Veins
collect nutrients from digestive organs and shunts them to the liver
Nerve Supply Of GI Tract
enteric (means digestive) nervous system (gut brain) regulates digestive system activity
Myentreric Nerve Plexus
sandwhiched between longitudinal and circular layers of muscularis externa
Submucosal Nerve PLexus
located with submucosa
Short Reflexes
mediated entirely by enteric NS
Long Reflexes
mediated by enteric NS and autonomic division of CNS via sympathetic and parasympathetic neurons
Mouth
mucosa (lining) is stratified squamous epithelium; bounded by lips cheeks and palate; soft palate closes off nasopharynx when swallowing; continous with oropharynx; accessory organs include tongue, salivary glands, and teeth
Tongue
bundles of skeletal muscle; mixes food with saliva to form a bolus (compact mass); initiates swallowing; upper surface covered with papillae; root of tongue has lingual tonsil
Intrinsic Tongue Muscles
change shape of tongue
Extrinsic Tongue Muscles
alter tongue position (front, back, left, right)
Filliform Papillae
most numerous; roughen tongue surface
Fungiform, Vallate and Foliate Papillae
possess taste buds
Lingual Frenulum
anchors tongue; children born with a short frenulum (ankyloglossia) are “tongue tied”
Parotid Salivary Gland
anterior to ear; contains serous cells
Submandibular Salivary Gland
media aspect of mandibular body; contains serous cells
Sublingual Salivary Glands
under tongue; contains primarily mucous cells (produce mucus)