Metabolism and energy exchange
Answers are for parents and teachers.
1
Write the stages of metabolism in order.
Digestion → absorption → transport by blood → cell metabolism → excretion.
2
Tabulate the functions of protein, carbohydrate and fat.
Protein – building, enzymes; carbohydrate – main energy, glycogen; fat – energy reserve, membranes, protection.
3
Write 4 functions of water and mineral salts in the body.
Reaction medium; transport; temperature control; salts for bones, haemoglobin and nerve–muscle function.
4
List the sources of protein, carbohydrate and fat in your day’s food (do not write amounts).
For example: egg, milk, meat – protein; bread, rice, potato – carbohydrate; oil, nuts – fat.
5
Why is mixed eating recommended rather than one kind of food?
Different nutrients and vitamins are needed; foods complement each other.