ð Takes in Food (mouth) ð Hydrolyzes macromolecules to their basic units. (see next slide) ð Absorbs the broken down food into the blood stream which delivers it to your tissues and organs.

Carbohydrate Digestion Salivary amylase (made by salivary glands)…works in mouth Pancreatic amylase (made by pancreas)…works in small intestine Maltase (made by small intestine)…works in small intestine Lactase (made by small intestine)…works in small intestine Protein Digestion Pepsin (made by stomach)…works in stomach Trypsin (made by pancreas)…works in small intestine Peptidases (made by small intestine)…works in small intestine Fat Digestion Lipase (made by pancreas)…works in small intestine Nucleic Acid Digestion Nuclease (made by pancreas)…works in small intestine Nucleosidases (made by small intestine)…works in small intestine

CHEWING CHEWING: breaks food into smaller pieces (increases surface area) “Mechanical” digestion (20 baby teeth, 32 adult) SALIVA SALIVA: slightly basic SWALLOWING SWALLOWING: soft palate is pushed up to close nasal passages, trachea moves up under the epiglottis to close the glottis. PERISTALSIS PERISTALSIS: muscle contraction that moves food through the digestive tract. Moves food from mouth to stomach in 5-8 seconds. Lower Gastroesophageal Sphincter: Lower Gastroesophageal Sphincter: entrance of esophagus to stomach. Food passes when relaxed.

Stores food and initiates digestion of protein. Very muscular. It contracts to mix food,”mechanical digestion” Lined with millions of glands that secrete HCl (acidic) and Pepsin (enzyme) “chemical digestion” Food stays there for 2-4 hours Gastric bypass attaches the upper part of the stomach to the middle of the small intestine.

Structure Structure:  Muscular tube about 6m long  “Small” because of its diameter  Duodenum (first 25 cm) of small intestine…this is where enzymes from the pancreas and liver are collected.  Bile from the liver causes fat droplets to disperse in water. Since the fat molecules are smaller, lipase can now work.  This is where nutrients are absorbed into the blood.  Food stays in the small intestine for 3-5 hours.

Also known as the “Colon” Only contains things that can’t be digested…waste 1.5m long and 6.5cm wide Water is absorbed into the blood here Bacteria live in here to further break down matter, produce B complex vitamins (coenzymes) and most of the vitamin K (needed for blood clotting) needed by our bodies

/ hours in the large intestine before the feces reaches the rectum and leaves the anus. Total time it takes to digest is hours