3.3 Break it down!

• Biologie
• Middelbare school
• havo
• Leerjaar 3

Lesson plan

Read 3.3: p. 73 up to p.75

Join the class 2B (link in teams)

Prior knowledge

Explanation 3.3

Work on exercises: 33-35, 38-43

Homework:

Study 3.3 + do exercise 33-35

Why should pregnant women eat a lot of protein?

Which of the following is not a function of fat?

1. Protect inner organs
2. Help to absorb vitamins
3. Building block
4. Protect against disease

Which of these food products are high in protein?

1. Salmon
2. Vegetable oil
3. Blueberries
4. Oatmeal

Why is it hard to determine what is 'healthy food'?

'The BMI is a great indication of someone's health'. Agree / Don't agree? Explain why!

3.3 Break it down!

ingestion-digestion-absorption-elimination

digestion

mechanical => chewing

chemical  => breaking food down using enzymes

enzymes 

substrate is broken down

Enzymes

Chemical digestion

Enzymes: Important chemicals

Chemical digeston step 1: 

• the place: the mouth (oesophagus)
• the enzyme: amylase
• the liquid: saliva
• the nutrient: carbohydrates
• the products: glucose & maltose

• The enzymes in your saliva start breaking down the carbohydrate molecules into maltose and glucose.

Chemical digeston step 2: 

• the place: the stomach
• the enzyme: protease
• the liquid: chyme and hydrochloric acid
• the nutrient: proteins
• the products: amino acids

• The enzymes in your chyme start breaking down the protein molecules into amino acids.

Chemical digeston step 3: part A

• the place: the duodenum
• the enzyme: lipase
• the liquid: chyme and bile
• the nutrient: fats
• the products: fatty acids and glycerol

Do exercises

3.3: 33-35, 38-43

Ingestion

Mechanical digestion

Chemical digestion

MOVING THE FOOD INTO YOUR MOUTH

BREAKING THE FOOD INTO SMALLER PIECES.

THIS IS DONE BY YOUR TEETH

BREAKING THE FOOD INTO EVEN SMALLER PIECES.

USING ENZYMES TO BREAK DOWN THE FOOD MOLECULES. 

What is the end product matching the enzyme called 'protease'?

1. Amino acids
2. Protein
3. Fatty acids
4. Nutrients

What is the difference between mechanical and chemical digestion?