1. The Digestive System: Secretion of Digestive Juices By Yoshi (Erin) and Mads (Maddie)

2. Salivary Glands  Salivary glands secrete saliva.  This saliva contains amylase, an enzyme that turns starch into glucose.  Saliva serves in beginning the breakdown of carbohydrates.  It also contains bicarbonate ions, which neutralizes acids in the foods.

3. Gastric Glands  Located in the epithelial cells in the stomach, these gastric glands secrete gastric juices.  Secretion of gastric juices is controlled by nervous (smells, thoughts, caffeine) and endocrine signals.  The stomach secretes 400-800 mL of gastric juices per meal  The gastric juices contain HCL, which lowers the pH in the stomach to between 1.5 and 2.5, thereby activating pepsin.  HCL also kills microorganisms which may be living in the food.  Pepsin is released from the breakdown of pepsinogen which serves as a stable storage for HCL and pepsin so that it is not released when there is no food in the stomach.  Pepsin serves as an enzyme that begins protein digestion in the stomach, and it works by splitting off fragments of peptides from protein molecules during digestion in the stomach.

5. Pancreatic Glands  Pancreatic juice is secreted into the small intestine at the duodenum.  The pancreatic juice neutralizes the chyme, using sodium bicarbonate, an acid neutralizer.  The juice contains digestive enzymes: Pancreatic amylase, which hydrolyzes starch Pancreatic lipase, which hydrolyzes ingested fats

6. Small Intestine  The villi in the small intestine have cells that produce enzymes which complete the digestion of both peptides (protein) and sugars (carbohydrates)