Digestive System Study Guide

BODY SYSTEMS

a) Describe the role of the digestive, circulatory, respiratory and the renal system.

b) Describe the roles of the parts of each system, and any feature that help them to carry this out.

1. DIGESTIVE SYSTEM

Digestive system is uniquely established to perform specific roles. There are two types of digestion:

• Mechanical digestion: starts in the mouth, when food is chewed is broke in small pieces.

• Chemical digestion: The main function of this system is to covert food into small molecules, like: amino acids, fatty acids or glucose, these molecules of foods are then absorbed from the small intestine into the blood stream and delivered to blood cells. From where does it start and finish?

 Start from the mouth that include:

a)

It intakes about 9 litres of fluids on daily basis.

• The jejunum: Both of them, absorbs food molecules by villi into the blood

• The ileum: stream.

Pancreas: Pancreas plays an important role in the digestion system, it alter the food into molecules so that they will be used by the cells.

• It produce enzyme= helps to divide the lipids, protein and carbohydrates molecule.

• It make the insulin (hormone) = helps to adjust the blood glucose amount.

• It makes sodium bicarbonate= which helps to balance acids present in stomach.

Liver: The liver is a very big organ, is situate above the stomach. It produce bile, which allow the digestion of fats (lipids). Gallbladder, is where the bile is stored. From the gallbladder, the bile is then moved into the duodenum (an organ of small intestine) where it digest lipids (fats).

Large Intestine: The main function of the large intestine is to discard undigested material and water. The chemical digestion send all the remaining material (without nutrients). Water is eliminated from the material through villi and return to the blood