Term
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Definition
GI tract
digests food and absorbs digested fragments through lining into blood
organs: mouth, pharynx, esophagus, stomach, small intestine, large intestine |
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Term
accessory digestive organs |
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Definition
organs: teeth, tongue, gall-bladder, digestive glands (salivary glands, liver, pancreas)
produce a variety of secretions that contribute to he breakdown of foodstuffs |
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Term
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Definition
1. ingestion
2. propulsion
3. mechanical digestion
4. chemical digestion
5. absorption
6. defecation |
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Term
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Definition
major means of propulsion
alternate waves of contraction + relaxation of muscles, mainly to squeeze food along the tract |
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Term
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Definition
rhythmic local constrictions of the small intestine
mixes food w/ digestive juices and increases efficiency of absorption by moving different parts of food over intestinal wall |
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Term
| Digestive activity is provoked by a range of mechanical and chemical stimuli. |
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Definition
mechanoeceptors + chemoreceptors are located in walls of tract organs and respond to several stimuli
respond to stretching of organs by food, osmolarity + pH of contents, and presence of substrates and end products of digestion
When activated, receptors:
--activate or inhibit glands that secrete digestive juices or hormones into blood
--stimulate smooth muscle of GI tract to mix lumen contents + move them along the tract |
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Term
| Controls of digestive activity are both intrinsic and extrinsic. |
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Definition
Nerve fibers that excite smooth muscle secrete acetylcholine or Substance P
those that inhibit smooth muscle released vasoactive intestinal peptide or nitric oxide |
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Term
| Intrinsic Controls of Gut |
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Definition
| product of “in-house” nerve plexuses or hormone producing cells |
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Term
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Definition
| enteric nerve plexuses that are along entire length of GI tract |
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Term
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Definition
| mediated entirely by local gut plexuses in response to stimuli |
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Term
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Definition
| initiated by stimuli arising inside or outside the GI tract and involve CNS centers and extrinsic autonomic nerves |
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Term
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Definition
| most extensive of membranes, lines abdominal cavity and viscera, transparent membrane |
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Term
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Definition
| covers external surfaces of most digestive organs and is continuous w/ parietal peritoneum that lines body wall |
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Term
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Definition
| between the visceral and parietal peritonium and has slippery fluid, which lubricates mobile digestive organs and allows them to glide as they do digestive duties |
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Term
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Definition
double layer of peritoneum that extends to digestive organs from body wall
basically anchors it to body wall.
Provides routes for blood vessels, lymphatics, and nerves to reach viscera
holds organs in place + stores fat
is dorsal in most places and attach to dorsal wall
ventral mesentaries are like ones that are from liver to anterior abdominal wall
Some have specific name or are called ligaments
Not all alimentary canal organs suspended by mesentery
Some parts of the small intestine adhere to dorsal wall and lose their mesentery
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Term
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Definition
| most of the pancreas and parts of the large intestine |
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Term
| Intraperitoneal / Peritoneal Organs |
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Definition
| Digestive organs that keep their mesentery and remain in the peritoneal cavity |
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Term
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Definition
inflammation of peritoneum
can arise from piercing abdominal wound, perforating ulcer, poor sterile technique during abdominal surgery; most commonly burst apendix
peritoneal coverings tend to stick together around the infection site, localizing the infection for macrophages to attack
If becomes widespread within peritoneal cavity, dangerous and lethal
Treatment: removing as much infectious debris as possible and administering megadoses of antibiotics
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Term
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Definition
| arteries that branch off abdominal aorta to serve digesive organs and hepatic portal circulation |
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Term
| Walls of Alimentary Canal |
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Definition
| mucosa, submucosa, muscularis externa and serosa |
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Term
| Mucosa of Alimentary Canal |
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Definition
mucous membrane, simple columnar with goblet cells
innermost layer
moist epithelial membrane that lines aliementary lumen from mouth to anus
1. serete mucus, digestive enzymes, hormones
2. absorb end products of digestion into blood
3. protect against infectious disease |
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Term
| Submucosa of Alimentary Canal |
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Definition
External to the mucosa
areolar CT
rich supply of blood + lymph vessels, lymph follicles, nerve fibers
elastic fibers enable stomach to regain normal shape after temporarily storing stuff
Extensive vascular network supplies surrounding tissues of GI tract wall |
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Term
| Muscularis Externa of Alimentary Canal |
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Definition
surrounding submucosa
called muscularis
responsible for segmentation and peristalsis
inner circular layer and outer longitudinal layer of smooth muscle cells
circular layer thickens in some areas and form sphincters |
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Term
| Serosa of Alimentary Canal |
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Definition
protective outermost layer of intraperitoneal organs
areolar CT covered with mesothelium, single layer of squamous epithelial cells
in esophagus, serosa replaced by adventitia, which is fibrous CT and binds esophagus to surrounding structures
retroperitoneal organs have both a serosa (side facing peritoneal cavity) AND adventitia (side abutting dorsal body wall) |
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Term
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Definition
| outermost layer of epithelial tissue encasing a visceral organ |
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Term
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Definition
occupies submucosa
includes sensory and motor neurons
regulates activity of glands and smooth muscle in mucosa |
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Term
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Definition
| inbetween circular and longitudinal muscle layers in muscularis externa |
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Term
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Definition
| anterior opening of mouth |
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Term
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Definition
| posterior opening of mouth |
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Term
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Definition
| recess bounded externally by lips and cheeks and internally by gums and teeth |
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Term
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Definition
| the area that lies within teeth and gums |
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Term
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Definition
| reddened area where we apply lipstick |
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Term
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Definition
| median fold that joins internal aspect of each lip to the gum |
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Term
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Definition
| forms roof of the mouth and has two parts: hard palate and soft palate in the back |
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Term
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Definition
| forms a rigid surface against which the tongue forces food during chewing, front area |
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Term
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Definition
| Midline ridge of palate to create fiction during chewing |
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Term
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Definition
| mobile fold formed mostly of skeletal muscle that has a reflex to close off nasopharynx when we swallow |
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Term
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Definition
| anchors soft palate to the tongue |
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Term
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Definition
| anchors soft palate to wall of oropharynx |
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Term
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Definition
| projects from the free edge of the soft palate |
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Term
| Intrinsic Muscles of Tongue |
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Definition
| in the tongue and not attached to bone, allow tongue to change shape to become thicker, thinner, longer, or shorter for speech and swallowing |
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Term
| Extrinsic muscles of tongue |
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Definition
| extend to tongue from points of origin on bones of the skull or the soft palate, extrinsic muscles alter tongue’s position: protrude it, retract it, and move it from side to side |
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Term
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Definition
| a fold of mucosa that secures the tongue to the floor of the mouth and limits pr movements of the tongue |
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Term
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Definition
| where children are “tongue tied” because frenulum restricts movement |
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Term
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Definition
gives tongue roughness, aids in licking semi-solid foods, provides friction for manipulating food
smallest + most numerous, parallel at back of tongue, have keratin and makes tongue look white |
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Term
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Definition
| are all over the tongue, look red |
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Term
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Definition
| are in a V-shaped row at the back of the tongue |
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Term
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Definition
| are on the lateral aspects of posterior tongue |
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