3 internal Systems:
Digestive system (Breakdown nutrients absorb nutrient) includes: Salivary Glands-Tongue-Epiglottis- Esophagus-Liver-Stomach-Gall Bladder- Duodenum-Pancreas-Jujunem (small intestine)- large intestine (colon)- Illeum (small intestine)- Appendix- Rectum- Anus.
Digestive: its main function is to breakdown macromolecule like carbs, proteins, lipids, and nucleic acids.
The digestion includes 4 stages:
Ingestion (gets nutrients into the body)
Digestion (mechanical, chemical)
Absorption (gets nutrients into the blood)
Excretion (Egestion) (waste removal)
Lipids: waxes-fats-cholesterol steroids-phospholipids.
Carb: Monosaccharide: glucose-fructose, lactose Disaccharide: sucrose, galactose
Proteins: muscle – enzymes
Nucleic acids : DNA-RNA-ATP Polysaccharide: glycogen, cellulose
15-18 male = 2800 cal/day
15-18 female = 2100 cal/day
Pregnant women = +300 cal/day
Breast feeding women = +500 cal/day
Water is 90% H2O
Enzymes are proteins and are called catalysts that speed up a chemical reaction Macromolecule | Smallest Unit | Carbs | Monosaccharide | Proteins | Amino Acids | Lipids | 1 glycerol/3 fatty acids |

Amylase is an enzyme found in the salivary glands and breaks down food.
Tongue pushes food to the pharynx and then to the esophagus
Digestion/Absorption: takes 2-24 hours in stomach –it has pepsin enzyme and a pH of 1-2 (active digestion) 3-4 ( inactive)
Small intestine= chime (food) is mixed with bile
The organs that make up the GI tract are the mouth, esophagus, stomach, small intestine, large intestine—which includes the rectum—and anus. Food enters the mouth and passes to the anus through the hollow organs of the GI tract. The liver, pancreas, and gallbladder are the solid organs of the digestive system.
Certain bacteria in the large intestine make vitamin K, which the body needs for blood clotting.
When