THE HUMAN DIGESTIVE SYSTEM

What happens to food after you eat it? Click on each of the organs to find out about their role in the digestive system!

The journey begins here… Down Click on each organ to reveal more information about it! MOUTH 2 TYPES OF BREAKDOWN OCCUR IN THE MOUTH: Mechanical breakdown: The teeth chews food into smaller pieces before swallowing. Chemical breakdown: The salivary glands produce enzymes which helps to break down food. The journey begins here…

Up Down It is a muscular tube that pushes the food down into the stomach. The walls of the oesophagus contract (squeeze together) to aid the movement of food from the mouth to the stomach. This allows food to be swallowed even while we are lying down! OESOPHAGUS

LIVER STOMACH GALL BLADDER SMALL INTESTINE PANCREAS LARGE INTESTINE Up Down It produces bile required to emulsify lipids (fats) in the small intestine. The stomach has muscles that crush and squash what we eat and drink. The food also mixes with digestive juices, which contain enzymes that chemically break down food. Proteases: for breakdown of proteins Lipase: for breakdown of lipids (fats) Amylase: for breakdown of carbohydrates GALL BLADDER It stores bile between meals and releases it through the bile duct into the small intestine to help in the digestion of lipids (fats). SMALL INTESTINE PANCREAS The small intestine is a long (about 7.5m), hollow tube that snakes around the abdomen. The lining of the small intestine is made up of tiny fingers called villi. Villi contain small blood vessels that collect nutrients. In the small intestine, proteins are further broken down by enzymes produced in the pancreas and fats are emulsified by bile produced in the liver. It produces pancreatic juice required to digest proteins and carbohydrates. The juice is released through the pancreatic duct into the small intestine. LARGE INTESTINE The food not taken into the bloodstream by the small intestine travels into the large intestine. It is shorter than the small intestine, at about 1.5 m. Water is absorbed

APPENDIX RECTUM AND ANUS Up Recent research suggested that the appendix serves as a reserve for good bacteria that the body can use when required. Undigested food is stored in the rectum as waste, this comes out of the anus as faeces.

Have you learnt much about the human digestive system?