CHAPTER 48 SECTIONS 1 & 2 PP DIGESTIVE SYSTEM Warm-up: 5/14 What is the pathway for the respirator system, starting with the mouth and ending with the lungs? Draw and label the 4 chambers of the heart.

FUNCTION Breakdown of food into simpler molecules that can be absorbed by the body in one long tube from mouth to anus

NUTRIENTS 6 classes of nutrients: 1.Carbohydrates 2.Fats 3.Proteins 4.Minerals: help balance osmosis and the function of certain cells (i.e. muscle cell) 5.Vitamins: aid enzyme activity 6.Water: accounts for half of your body weight

PATHWAY Mouth  Pharynx  Esophagus  Stomach  Small Intestine  Large Intestine (colon)  Rectum

MECHANICAL VS. CHEMICAL DIGESTION Mechanical: physical breakdown of food Chewing, peristalsis (moving bolus down the esophagus), and stomach churning

MECHANICAL VS. CHEMICAL DIGESTION Chemical Digestion: Enzymes breaking down food into simpler forms (monomers)

DIGESTIVE TRACT MOUTH AND ESOPHAGUS Amylase (enzyme) is released from glands into saliva Function: Breaks down carbs to sugars Bolus (food ball) travels down esophagus to stomach

STOMACH Muscle contractions break bolus apart Pepsin (enzyme) breaks down proteins HCl (Hydrochloric acid) keeps stomach acidic so the pepsin can work

LIVER Produces bile and secretes it into the stomach Bile breaks down fats

SMALL INTESTINE Chemical and nutrient absorption

GALL BLADDER Stores bile and secretes it into the small intestine

PANCREAS Secretes sodium bicarbonate (base) into small intestine to neutralize acid

LARGE INTESTINE/COLON Absorption of water, minerals, and vitamins

Salivary glands StomachLiver Pancreas Gall bladder Small intestine Large intestine/colon Esophagus