3.3 Break it down!

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• Middelbare school
• havo
• Leerjaar 3

3.3 Break it down!

Lesson goals

In the end of the lesson: 

• I can describe the four stages that the body goes through to process food.
• I can mention what are enzymes and why do we need them.

ingestion-digestion-absorption-elimination

Digestion

mechanical => chewing

chemical  => breaking food down using enzymes

enzymes 

substrate is broken down

Amylase

Make exercises

Read chapter 3.3 (pg. 73) and make 33-35, 39-41 and 43 (WB).

Homework: Read page 76 -81 (Very important!)

Lesson goals

In the end of the lesson: 

• I can describe the four stages that the body goes through to process food.
• I can mention what are enzymes and why do we need them.

Chemical digestion 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 digestion 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.

Before chemical digestion step 3: 

• the place: liver
• the enzyme: none
• the liquid: bile
• the nutrient: fats
• 
  
• Bile emulsifies (breaks chemical bonds) fats.

Chemical digestion 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

0

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

Fases of digestion. Put them in the right order.

1

2

3

4

digestion

ingestion

absorption

egestion

What is the difference between mechanical and chemical digestion?