exam 2 class 15 Flashcards
stopped at slide 20 (41 cards)
Digestive system begins with?
oral cavity (mouth and pharynx), which serves as a receptacle for food
Swallowed food enters
gastrointestinal tract
(GI tract)
gastrointestinal tract
(GI tract) consisting of
esophagus, stomach,
small intestine, and large intestine
Portion of the GI tract running from the
stomach to the anus is also called the
gut
Digestion, chemical and mechanical breakdown of food, takes place primarily in?
lumen of gut
Secretions are added to ingested food by?
secretory epithelial cells and by accessory glandular organs
accessory glandular organs that include?
salivary glands, liver,
gallbladder, and pancreas.
(1) Sublingual glands
under the tongue
(2) Submandibular glands
under the mandible (jawbone)
(3) Parotid glands lying near
the hinge of the jaw
Swallowed food passes into
__________, a narrow tube that travels through the ________ to _________
esophagus
thorax
abdomen
Esophageal walls are _______ initially but transition to
__________ about two-thirds of way down length
skeletal muscle
smooth muscle
Stomach has three
sections:
upper fundus,
central body,
lower antrum
opening between stomach
and small intestine is
guarded by the pyloric
valve
Pylorus {gatekeeper}
Stomach continues digestion that began in the
mouth by mixing food with acid and enzymes to
create?
chyme
Most digestion takes place in
small intestine
what are the three sections of the small intestine
duodenum (the first 25 cm),
jejunum,
ileum
______________is carried out by intestinal enzymes, aided by exocrine secretions from
two accessory glandular organs: pancreas
and liver
Digestion
Digestion finishes in ?
small intestine,
proximal section of large
intestine—watery chyme becomes semisolid
feces, as water and electrolytes are absorbed out of the chyme and into the extracellular fluid
(ECF)
in the colon
(1) inner mucosa facing lumen
(2) submucosa
(3) layers of smooth muscle known collectively as muscularis externa
(4) covering of connective tissue called serosa
4 layers of the GI tract
what does the Mucosa include:
(1) transporting epithelial cells (called enterocytes in the small intestine),
(2) endocrine and exocrine secretory cells,
(3) stem cells
what is done at the mucosal surface
cells secrete ions, enzymes, mucus, and paracrine molecules into lumen
tie GI epithelial cells together
cell to cell junctions