4Tongue Places food during chewing Papillae contain taste buds Multiple blood vessels under tongue = high absorption of soluble drugs into circulationEx. Nitroglycerin pills for heart attack,Vitamins
5Salivary Glands Parotid = largest Submandibular Sublingual = smallest Located in front of and below earProduces watery substance with enzymesSubmandibularLocated below mandibular angleProduces enzymes and mucusSublingual = smallestUnder floor of mouthProduces mucous type of saliva
6Salivary Glands: Function Begins the break down of food through hydrolysis.Carbohydrate digestion begins in the mouth with aid of saliva.
7Teeth Crown - exposed covered with enamel Neck - surrounded by gums (gingiva)Root - fits into socket
8Teeth Coverings Enamel - Hardest substance in body Dentin - tissues, nerves, blood vesselsCementum - covers dentin
10Dentition Permanent Teeth 32 Total Adult teethSecondary teeth32 Total3rd set of molars come in after age 17 (wisdom teeth)
11Other Organ Components PharynxReceives bolus (rounded mass of food)Carries bolus to esophagusEsophagusCollapsible tube that enters the stomachPosterior to trachea and heartProtected by a thick layer of mucus
12Esophagus ContinuedFood (Bolus) moves through the esophagus and the rest of the alimentary canal by peristalsis - involuntary muscle contractions.
13Stomach Located below diaphragm and liver Enlarges after meals then collapsesSize of large sausage
14Stomach Divisions Fundus - large portion at end of esophagus Body - central portionPylorus - lower portion near small intestine
15Sphincter Muscles Guard openings to stomach Cardiac - esophagus to stomachPyloric - lower portion of stomach to small intestine.Pylorospasm - muscle will not relax to allow passage of bolus = vomiting
16Stomach Function Food storage Secretion of gastric juices Churning of food and breakdown into chyme - liquid food.Absorption = water, alcohol, and drugsGlands of stomachGastric - secret gastric juiceMucus - contains enzymes and hydrochloric acid.
17Small Intestines 20 feet long Divisions Duodenum = uppermost area, attaches to stomach.Jejunum = middle areaIleum = end portion, leads to large intestine.All set in place by mesentery (membrane)
18Small Intestines Continued This is where most digestion occurs.Absorption of digestive products.Inside surface of small intestines covered with tiny projections called villi.1mm projectionsIncrease surface area by 160x
19Large Intestines 5-6 feet long Divisions Ascending colon - right side of abdomenTransverse colon - horizontally across abdomen and under liverDescending colon - left side of abdomenRectum - last 7-8 inchesAnus - contains many arteries and veinsHemorrhoids - enlargement of veins in anal canal.
20Large Intestines Continued Water/electrolyte absorptionForms/stores feces
21Large Intestines Continued AppendixLocated just behind cecumNo functional importance in digestion.Appendicitis = inflammation of the appendix
22Accessory Organs Liver structure Liver function Largest gland in body Under diaphragmAble to regenerateLiver functionDetoxifies many substancesMakes and secretes bileMetabolizes proteins, fats, and carbs
23Accessory Organs Gall bladder Stores bile, increases its concentration Bile breaks down fat.During digestion, empties bile into small intestines