2.3 - Eating disorders and 2.4 - The digestive system

• Biologie
• Middelbare school
• vwo
• Leerjaar 2

Today's lesson

1. Discuss HW questions

2. Eating disorders

3. Begin the Digestive System

Eating disorders

Anorexia nervosa:  lose extreme amounts of weight

Bulimia nervosa:  vomit to get rid of the food, use large amounts of laxatives

Binge eating disorder: moments of eating a lot 

2.5 The digestive system

2.6 The digestive system

Digestion

Digestion: Breakdown of food molecules into small food molecules 

When food is digested it is absorbed  

Big vs. Small

Big molecules -> Insoluble can not get through the gut wall

Small molecules -> Soluble can get through the gut wall

Fases of digestion. Put them in the right order.

1

2

3

4

digestion

ingestion

absorption

egestion

FASES OF DIGESTION:

• INGESTION
• CHEMICAL AND MECHANICAL DIGESTION
• ABSORPTION
• EGESTION

CHEMICAL DIGESTION:

• BREAKING THE FOOD INTO EVEN SMALLER MOLECULES.
• USING ENZYMES TO BREAK DOWN THE FOOD MOLECULES. 

Chemical digestion

Enzymes: Important chemicals

Down the tube!

Oesophagus

Peristalsis: moving food down your oesaphagus (gullet)

Work

Go to classroom and follow the link 'draw a model of the digestive system'.

• Draw the organs of the digestive system
• label the parts
• add the functions