Quiz 9 Flashcards
What is the digestive system?
aka alimentary canal; stomach as organ, villi as basic unit; about 30 feet long with two openings (mouth/stomadeum, anus/proctadeum); includes mouth, esophagus, stomach, small intestine, and large intestine
Gut Wall: made of serosa (outer; 100% epithelium). muscle (visceral, ANS, peristalsis), mucus (sticky), sub-mucus (innermost; wavy)
What is the mouth?
aka stomadeum, buccal/oral cavity; 5% of total digestion, breaks down carbohydrates into saccharides
MECHANICAL: teeth for chewing; tongue, glossal, lingual for mixing food bits and saliva
CHEMICAL: salivary glands that produce enzymes
- Parotid: squirts; profuces ptaylin (monosaccharide)
- Tongue
- Sub-lingual: under tongue; produces lipase (lipid)
- Sub-mandibular: under jaw; produces amylase (dominant; polysaccharides; breaks down into glucose, level should be under 100 parts per million; stored as glycogen in liver)
- Pharynx: back of mouth; beginning of esophagus
What is the esophagus?
1, 2
connects pharynx to stomach; 0% digestion; about one foot long, but tri-innervated (CNS, control - ANS/CNS, some control - ANS, no control)
- Esophagus
- Cardiac Sphincter: located at the end of the esophagus, right above the stomach; regulates amount of food that enters stomach
What is the stomach?
3, 4, 5, 6, 7
use mainly as food resevoir; 100% visceral muscle; about one gallon in volume; 5% of total digestion, breaks down proteins into proteins
Deamination: proper digestion of proteins in the stomach; produce creatinine and urea; dairy is dissolved by renin; meat is dissolved by pepsin; fats are dissolved by lactase
Omentum: lesser/superioir, greater/inferior; keep shape of stomach
- Cardid
- Rugae: muscular folds of the stomach; lined with cells; pit under; parietal epithelial (produce gastrin) cells; chief cells (produce hypochloric acid of a pH 2-3)
- Fundus
- Pylorus: has villi
- Pyloric Sphincter: regulates the amount of food that enters the small intestine
What is the small intestine?
1, 2, 3
90% of total digestion; cotains all enzymes and decreasing amount of villi; divided into duodenum (most active), jejunum (somewhat active), and ileum (least active)
- Ileocecal Sphincter: regulates amount of food that enters the large intestine
- Appendix: non-functional in humans
- Cecum: indicates beginning of large intestine
What is the large intestine?
4, 5, 6, 7, 8, 9
aka colon; 0% of total digestion; reabsorbs salt and water
Formation of Feces: probiotic bacteria mis fibers and undigested food together to make a solid mass
- Ascending Colon
- Transverse Colon
- Descending Colon
- Sigmoid: s-shaped structure near end of colon
- Rectum: pocket before the anal sphincter
- Anal Sphincter: regulated smount of waste that leaves the body
What is symbiosis? What are the three types?
two different organisms that live together
- Commensalism: one benefits; the other is unharmed
- Mutual: both benefit
- Parasitic: one benefits; the other is harmed
Define mastication, deglutination, distension, bolus, and chyme.
Mastication: to chew
Deglutination: to swallow
Distension: to expand
Bolus: semi-digested food within the mouth
Chyme: semi-digested food within the stomach
Define ulcer, sphincter, appendicitis, and lactose-intolerant.
Ulcer: hole that has been eaten away by acid or gird-acid reflex
Spincter: strong muscular valve of ANS innervation
Appedicitis: inflammation of the appendix that causes sharp pains and fevers; may lead to death if ruptured
Lactose-Intolerant: lack of lactase enzyme
