Chapter 5: Food and Humans

Question 1

Why do we need to take in food everyday?

Answer 1

It is because food provides us with:
* Energy for supporting daily activities and keeping us warm.
* Raw materials for growth and repair of body tissues.
* Substances that are important for maintaining health.

Question 2

What are the 7 types of food substances in food?

Answer 2

Carbohydrates, lipids, proteins, minerals, vitamins, dietary fibre, water

Question 3

What is ‘condensation’?

Answer 3

Condensation is a chemical reaction in which two molecules combine with loss of a water molecule.

Question 4

What is ‘hydrolysis’?

Answer 4

Hydrolysis is a chemical reaction in which one molecule breaks down into two molecules with the addition of a water molecule.

Question 5

What are the building blocks of carbohydrates?

+General formula

Answer 5

Carbon (C), hydrogen (H), oxygen (O)
General formula: Cx(H₂O)y (H:O = 2:1)

Question 6

How are disaccharides and polysaccharides formed from monosaccharides?

Answer 6

Disaccharides and polysaccharides are formed by joining monosaccharide molecules in condensation.

Question 7

How are monosaccharides formed from disaccharides and polysaccharides?

Answer 7

Disaccharides and polysaccharides are broken down into monosaccharides in hydrolysis.