Download How Do Cells Make Organisms The Digestive System All cells need

How Do Cells Make Organisms
The Digestive System
All cells need nutrients to survive. However the sandwich you eat cannot be used by the cells
of your little finger as it is. Organisms therefore have a system of organs that break food into
useable nutrients. This is called the digestive system. The digestive system is composed of a
number of organs all with different functions:
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Mouth:
Food is broken into smaller pieces by chewing. Saliva begins to break down
complex carbohydrates such as starch.
Oesophagus:
From Greek meaning carry and eat. Muscular tube that carries food to the
stomach.
Stomach:
Muscular organ that mixes food and breaks down proteins. Contains
hydrochloric acid and pepsin.
Liver:
Involved in the storage and distribution of food. Produces bile which breaks
down fats.
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Pancreas:
Contains enzymes that secretes chemicals that breakdown many different
substances. Also produces the hormone insulin.
Small Intestine:
Digestion of fats, carbohydrates and proteins is completed. Nutrients are
placed absorbed into the blood stream.
Large Intestine:
Water, vitamins and minerals are absorbed into the blood.
Appendix:
Plays a role in immunity. Twisted structure allows bacteria to accumulate.