The Digestive System

The Digestive System The digestive system has 3 main functions: It breaks down food into particles that the body can use. It absorbs nutrients into the blood. It eliminates waste from the body. Mouth Esophagus

The Digestive System Digestion can happen in two ways: Mechanical digestion: foods are physically broken down into smaller parts (like by teeth). Chemical digestion: Chemicals called ENZYMES break foods into their smaller “building blocks” (for example, starch gets broken down into sugar). Mouth Esophagus

The Digestive System MOUTH: your teeth break down food into smaller pieces (mechanical digestion). Saliva has enzymes that start chemical digestion. ESOPHAGUS: smooth muscles push food down to the stomach (peristalsis). Mouth Esophagus

The Digestive System Most digestion happens in the Stomach: Mechanical digestion occurs when the stomach muscles churn the food. Chemical digestion happens when stomach acid breaks down food. Mouth Esophagus Stomach

The Digestive System Liver, gallbladder and pancreas: produces & stores chemicals (enzymes) that help digest food in the small intestine. Mouth Esophagus Stomach Liver Pancreas Gallbladder

The Digestive System Small intestine: completes chemical digestion and absorbs nutrients for the body. The nutrients pass through the villi into blood vessels. Large intestine: water is reabsorbed by the body. Rectum: compresses waste into a solid form. Mouth Esophagus Stomach Liver Pancreas Gallbladder Small intestine Large intestine Rectum