BIOL 320: EXAM 3
31 Cards in this Set
| Front | Back |
|---|---|
|
GI Tract Function
|
digest and absorb food
|
|
GI Tract Organs
|
Mouth, pharynx, esophagus, stomach, small intestine, large intestine
|
|
Accessory organs
|
teeth, tongue, gall bladder, salivary glands, liver, pancreas
|
|
Ingestion
|
putting food into mouth
|
|
propulsion
|
Accomplished by the muscular layers of the GI tract, movement through GI tract
|
|
Mechanical digestion
|
breaking food apart physically
|
|
Chemical Digestion
|
chemical breakdown of food by enzymes and acid (takes place everywhere but large intestine)
|
|
Absorption
|
movement of nutrients from GI tract to blood or lymph
|
|
Defecation
|
elimination of indigestible waste
|
|
Intrinsic control
|
regulation of digestion by the local enteric nerve plexi
|
|
extrinsic control
|
regulation of digestion by the CNS; works through local enteric nerve plexi
|
|
Local enteric nerve plexi
|
affects smooth muscle of organ wall or gland, either stimulates or inhibits digestion
|
|
Visceral peritoneum
|
Covers GI tract organs
|
|
Parietal peritoneum
|
lines the body wall of the abdominopelvic cavity
|
|
Peritoneal cavity
|
located between and filled with serous fluid
|
|
Mesentery
|
double layer of peritoneum that extends from the body wall to the organs; stores fat; holds organs in place; allows blood vessels, lymphatics and nerves to reach the organs
|
|
Retroperitoneal organs
|
found outside the parietal peritoneum against dorsal body wall (lose mesentery during development)
|
|
Layers of GI tract
|
amina propria, epithelium, muscularis mucosae
|
|
submucosa
|
dense connective tissue layer, contains blood and lymphatic vessels, lymphoid follicles and glands. Innervates submucosal nerve plexi
|
|
Muscularis externa
|
typically smooth muscle (some skeletal in esophagus); 2 layers
|
|
Longitudinal layer of muscularis externa
|
peristalsis: propulsion
|
|
Circular layer of muscularis externa
|
segmentation: mixing
|
|
Serosa
|
protective outer layer of intraperitoneal organs(visceral peritoneum)
|
|
Extrinsic salivary glands
|
parotid, submandibular and sublingual glands
|
|
Intrinsic salivary glands
|
Buccal glands in mucosa (keep the mouth moist)
|
|
Saliva components
|
H2O, salivary amylase, defensins, lysozymes, electrolytes, metabolic waste
|
|
xerostomia
|
dry mouth
|
|
Deglutition
|
swallowing
|
|
Buccal phase
|
bolus is forced into the oropharynx voluntarily
|
|
Pharyngeal-esophageal phase
|
air passage is closed off, involuntarily controlled by medulla and pons
|
|
Regions of the stomach
|
Cardiac, fundus and body, pyloric
|
BIOL 320: EXAM 1