Key Terms
Also know
Gastric inhibitory peptide (GIP) - inhibits gastric secretion and slows gastric emptying.
Teeth
20 deciduous (baby), 32 permanent
Tooth layers outside-in
Enamel (hardest substance in body) - dentin - pulp cavity (nerves and blood vessels)
Intestinal phase
Duodenum partially stimulates, then inhibits gastric secretion via enterogastric reflex when chyme fills duodenum
Circular folds (plicae circulares)
Deep ridges in mucosa/submucosa; cause chyme to spiral, slowing movement 2. Villi: finger-like projections (0.5-1 mm); e
INTESTINAL GLANDS (crypts of Lieberkuhn)
Secrete intestinal juice (slightly alkaline pH 7.4-7.8); 0.95-1.9 liters per day
STRUCTURE
Cecum - ascending colon - transverse colon - descending colon
FECES COMPOSITION
Undigested residue, unabsorbed substances, millions of bacteria, shed epithelial cells, inorganic salts, water
Absorbable form
Monosaccharides only (glucose, galactose, fructose)
Absorption
Active transport via sodium co-transport; mainly in duodenum and jejunum; dipeptides and tripeptides enter cells then ar
Absorbable forms
Monoacylglycerides, free fatty acids, glycerol
How fat absorption works
1. Bile salts and phospholipids emulsify fat globules into tiny droplets (increase surface area for lipase) 2.
Short-chain fatty acids
Small enough to enter capillaries directly via simple diffusion; go to liver via hepatic portal vein.
Retroperitoneal organs
Duodenum, pancreas, ascending colon, descending colon, rectum - located behind the peritoneum.
PERITONITIS
Inflammation of peritoneum; occurs when alimentary canal wall is breached (perforated ulcer, ruptured appendix); life- t