1. Which foods would you take on a three-day walking holiday? You will have to carry all your food.

2. We get our energy from food. What do we use it for?

3. Arrange these activities in order. Start with the one that uses most energy.
a. swimming
b. sleeping
c. doing homework
d. walking
e. playing basketball

4. An ambulance arrives at an accident. Why might the paramedics give oxygen to a casualty?

5. Is respiration the same as burning? Make a table and list three ways in which they are alike and three ways in which they are different.

6. Describe how an oxygen molecule gets from your lungs to a cell.

7. Complete the table about oxygen and carbon dioxide:

8. When we exercise, our bodies change. Describe how these things change:
a. heartbeat
b. number of breaths each minute
c. the volume of each breath
d. the amount of oxygen taken in
e. the amount of carbon dioxide given out
f. the amount of energy that is used

9. Nadia works out that her food for one day contains 9700kJ of energy. Nadia’s father is an electrician. She works out that her dad’s food contains 15000kJ. Can you think of three reasons for the difference?

10.You read a magazine article about young people and dieting. The article says that exercise is more important than dieting. Can you explain why?