(Final) The Digestive System

• Biology
• Lower Secondary (Key Stage 3)

The Digestive System

Fill in the gaps:
The role of the digestive system is to break down _______, large molecules into ______, small molecules

Insoluble; Soluble

Soluble; Insoluble

Mixed; Separate

Hard; Soft

Insoluble; Soft

Hard; Insoluble

Match up the term to the correct definition

Insoluble

Soluble

Cannot be dissolved 

Can be dissolved

Why does food need to be digested?

1. So it can be absorbed into the blood
2. So it tastes better
3. So it can fit easier into the large intestine
4. To clean you insides

Match the organ to its function

Mixes food with saliva and grinds/tears food with teeth

To store waste

To squeeze into the stomach

Main site of digestion; soluble nutrients absorbed into blood

Mouth

Oesophagus

Rectum

Small Intestine

What is the function of the large intestine?

The mouth contains what that mixes with food to soften it?

1. Sulphuric Acid
2. Saliva
3. Blood
4. Urea

What acid is found in the stomach?

1. Sulphuric
2. Nitric
3. Hydrochloric
4. Acetic

What is removed from food in the large intestine?

1. Lipids
2. Salt
3. Bile
4. Water

What is another name for food waste after it has been digested?

1. Waste
2. Faeces
3. Litter
4. Bile

Match the function to the organ

Stomach

Small Intestine

Anus

Muscles mix food with digestive juices and acid

Digest all nutrients and absorb them into the blood

To push out faeces

What are the three nutrient types your body digests?

1. Carbohydrates
2. Lipids/Fats
3. Proteins
4. Minerals

Name one of the roles of lipids/fats in the body

What is general role of protein in the body?

1. For insulating organs
2. For preventing constipation
3. For dissolving toxins
4. For growth and repair

What is an enzyme?

Match the nutrient to the digestion product and the enzyme

Carbohydrate

Lipid/Fat

Protein

Product

Enzyme

Simple sugars

Carbohydrase

Lipase

Protease

Amino Acids

Glycerol and fatty acids

What are the two main places you can find protease in the digestive system?

1. Mouth; Small Intestine
2. Stomach; Small Intestine
3. Stomach; Large Intestine
4. Small Intestine; Rectum

What does lipase break down?

1. Lipids/Fats
2. Proteins
3. Lichen
4. Lithium

Carbohydrase breaks down carbohydrates into what?

Name a nutrient in the diet that is NOT a carbohydrate, lipid/fat nor protein