The Small Intestine

The start of the small intestine

Liver

Stomach

Gall bladder

PancreasSmall intestine

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Milk and Food Colouring Demo

Bile

Bile works like washing up liquid…it splits big fat globules up into small fat globules.

The Liver and the Gall Bladder

• The liver produces bile

• The gall bladder stores bile

• Bile splits big blobs of fat into smaller blobs which are easier for enzymes to digest

The Pancreas

• The pancreas produces and releases the enzyme lipase

• Lipase breaks down fats into fatty acids and glycerol

Fat Fatty acids + glycerolLipase

Now large insoluble food molecules have been broken down into small soluble molecules

Carbohydrate

e.g. starch

Fat Protein

Amylase Lipase Pepsin

Now large insoluble food molecules have been broken down into small soluble molecules

Carbohydrate

e.g. starch

Fat Protein

Amylase Lipase Pepsin

The Small Intestine• All the nutrients from digestion are absorbed by the

small intestine

• The surface of the small intestine is covered in villi

The Villi• Villi increase the surface area of the small intestine.

This means that more nutrients can be absorbed and faster.

Features of the villi

Good Blood Supply

The blood capillaries absorb simple sugars

and amino acids

Thin epithelium

The skin of each villus is only one cell thick, this

allows absorption to happen very fast.

Lacteal

The lacteal absorbs fatty acids and glycerol

The Large Intestine

Large Intestine

Rectum

Appendix

Large intestine

AppendixRectum

All that enters the large intestine is waste material and water.

The Large Intestine• The large intestine absorbs excess water from

the waste material

The Rectum• The rectum stores faeces until it is convenient to

expel it