1. DIGESTION “You are what you eat.”
Malnutrition Obesity
Bulimia, Anorexia Nervosa
Nutrition : process in which the body takes in and utilizes necessary food substances
Nutrients (6):
Carbohydrates:
quick energy ; sugars and starches; mono, di, polysccharides
Lipids :
fats; for stored energy ; necessary for the cell membrane
Proteins :
for maintenance and repair ; made of amino acids

2. Digestion: the breakdown of food
Vitamins:
Act as co-enzymes ; A, C, D, etc.
Minerals:
Aid in metabolism ; Ca, K, Na, etc.
Water:
Aid in chemical reactions
Calories: units of heat that “burn up” food
Digestion: the breakdown of food
Mechanical
Chemical
Alimentary Canal : a muscular hollow tube from mouth to anus (9 meters long)
Peristalsis

3. Tongue (with taste buds)
MOUTH:
Lips
Hard palate
Soft Palate
Uvula
Tongue (with taste buds)
Teeth (32 secondary): molars, incisors, bicuspids
Crown
Root
Cementum
Enamel
Dentin

4. Salivary Glands (3 types)
Contain saliva
With water and mucus
Softens food (Bolus)
With salivary amylase or ptylin (digests carbohydrates)
Pharynx: opening at back of mouth
Esophagus (10 inches –10 minutes)
Tube from the mouth to the stomach
Behind the trachea
No enzymes

5. J shaped organ on the upper left side Food remains there for 4 hours
STOMACH:
J shaped organ on the upper left side
Food remains there for 4 hours
Muscles called rugae
Gastric Juices (include acids and enzymes)
Pepsin (changes proteins into amino acids)
Renin (curdles milk)
HCl (kills bacteria)
Liquified food called chyme
Irritation in top portion of stomach: heartburn
Open sore in stomach lining: ulcer

6. Digested food remains there for 10-12 hours Necessary for life
SMALL INTESTINE:
Consists of 3 parts: duodenum (10”), jejunum (8 ft.), ileum(12 ft) = 21 ft. long
Digested food remains there for hours
Necessary for life
Function: absorption
Contains microscopic villi
Structure of villi increases surface area
With capillaries and lacteals
Enzymes released:
Sucrase, Lactase, Maltase

7. Pancreas: releases lipase (fats) and trypsin (proteins)
ACCESSORY ORGANS:
Pancreas: releases lipase (fats) and trypsin (proteins)
Behind the stomach
Liver: releases bile (green)
Largest organ in the body
No enzymes
Emulsification: physical breakdown of fats
Gall Bladder : stores bile
Hardened bile: gall stones

8. LARGE INTESTINE:
Also known as the colon; 4-5 ft. long; tubing with wider diameter than the small intestine
Ileocecal Valve: connects to the small intestine
Function: reabsorbs water; prevents dehydration
Haustra: pouches in the walls of the colon
3 parts: ascending colon, transverse colon, descending colon
Appendix: no known digestive function; lymphatic tissue
Rectum: muscle that pushes waste out of the anus
Internal/External Sphincters regulates defecation
Mass Movement (Defecation)
Feces: 75% H2O; bilirubin, biliverdin; bacteria (odor)

9. Digestive Conditions Ulcers (open sores in the stomach due to HCl)
Heartburn (irritation in the top of the stomach)
Appendicitis (inflammation of the appendix)
Colitis (a “nervous stomach”; colon swollen)
Diverticulosis (food caught in the pouches of the colon)
Cirrhosis of the Liver (liver gets dried out)
Jaundice (bile ducts blocked)
Hepatitis (inflammation of the liver)
Gall Stones (hardened bile)
Hemorrhoids (rectal blood vessels inflamed)
Constipation (too much water reabsorbed)
Diarrhea (too little water reabsorbed)

10. Digestive Conditions

11. Dissection of the Earthworm:
Phylum Annelid (earthworm)
Hermaphrodite: animal with male and female parts
Food: dirt, dead leaves, insects
Used by farmers: fertilize soil, create air spaces
Setae (bristles): on the ventral side of the body for movement
Clitellum: contains both male and female parts
Mouth, Pharynx, Esophagus
Crop: stores food (acts like a stomach)
Gizzard: grinds the food