LIVING THINGS AND DIGESTION

THE DIGESTIVE SySTEm

L.O. To describe the simple functions of the basic parts of

the digestive system in humans.

The Digestive SystemHow do we get from this…

…to this?

The Digestive System

The Digestive System zoomed inoesophagus (gullet, or food pipe)

stomachsmall intestine

large intestine

anusEach part of the digestive system has a different job to do:

colon

pancreas

The MouthThe mouth contains teeth.

These chew the food and break it into smaller pieces.

At the same time the saliva glands, at the back of the mouth and under the tongue,

produce saliva to help begin breaking down the food and make it easier to

swallow. (Try putting some bread in your mouth and chewing gently. After it tastes

sweet because things in your saliva are breaking it down already)

The tongue pushes food to the back of the mouth so you can swallow it.

The Oesophagus

The oesophagus, or food pipe, joins the mouth and the stomach.

Food is squeezed along this tube into the stomach by two

different sets of muscles.

The Stomach

The stomach is a bag of acid.

The acid in the stomach, and special chemicals called

enzymes break down the food even more.

Also the stomach walls contract (pull in) to

physically break the food down too.

The Liver

The liver produces bile which helps to absorb fats.

Bile is sent to the gallbladder to be stored.

The pancreas produces enzymes to break down fats, proteins and carbohydrates.

It releases them into the duodenum.

The Pancreas and Gallbladder

The gallbladder releases bile into the duodenum when

needed.

The Small Intestine At the very beginning of the small intestine is the duodenum where food is broken down by bile from the gallbladder and enzymes from the pancreas.

The small intestine is 6-7 metres long.

In the small intestine, the broken down food gets absorbed (taken into) into the blood so the

body can use it.

The walls of the small intestine are covered in tiny sticky out

bits called villi that help this to happen quickly.

The Large Intestine and Colon

The large intestine is about 1.5 metres long.

In the large intestine, the body absorbs a lot of water back from the

digested food.

The colon stores waste ready to be excreted

(leave the body).

Large Intestine

Colon

The Anus

At the end of the digestive system, the left over stuff that

the body can not use is excreted (leaves the

body) through the anus when you go to the

toilet.

(Optional) For more information you can look at the information sheet: Science - Task 3 (Optional) - Human Digestive System Information

Click on the link below and practise putting the digestive system together independently. https://www.sheppardsoftware.com/health/anatomy/digestion/digestion_game_2.htm

Tasks:• Label and explain the different parts involved in digesting food.

See: Science - Task 3 – Digestive System Task - Word Document• Extension: Complete the word search. See: Science - Task 3 –

Digestive System Extension Task - Word Document.