2.2 - the digestive system

• Biologie
• Middelbare school
• vwo
• Leerjaar 2

The digestive system

Today's lesson

1. Review HW/ Do Test Yourself 2.1 

2. What is digestion?

3. Discuss chewing

4. What are digestive juices?

5. Explain peristalsis

HW Review

What is digestion?

Fig. 1: digestive system 

Contains the intestinal tract: 

long piece of tubing from mouth 

to anus

To do: translate organ names into

Dutch

Digestion continued

• Function of digestive system?
• Nutrients from food absorbed into bloodstream
• What can be absorbed into the blood?
• Glucose, minerals, water vitamins
• What is missing?
• Proteins, carbohydrates and fats
• NEED TO BE DIGESTED FIRST

How is food digested?

• Digested: break down into small pieces
• 2 types of digestion: Mechanical and Chemical digestion
• Mechanical: chewing
• Function: break the food into little pieces so that the surface area is larger.

Chemical Digestion

• Breaking food into even smaller molecules
• How? 
• Use digestive juices made in the digestive glands
• Digestive juices contain enzymes.

Peristalsis

Food moves through lots of tubes : intestinal tract

• Oesophagus
• Duodenum
• Small and large intestines

peristalsis = muscle movements that push food through the intestinal tract

Peristalsis

HW

Read 2.2 - The digestion system

V: Qs 1 t/m 3, 5 , 6 and 8