© Oxford University Press 2011 IP1.7.5 Energy transfers 2 Energy transfers 2

© Oxford University Press 2011 IP1.7.5 Energy transfers 2 Do you think this Cape Fox is maximising or minimising energy transfer? How is it doing this?

© Oxford University Press 2011 IP1.7.5 Energy transfers 2 The cape fox has large ears. Blood is pumped through the ears and thermal energy is transferred to them. The large surface area of the ears maximises the transfer of this thermal energy to the surroundings of the fox.

© Oxford University Press 2011 IP1.7.5 Energy transfers 2 What about this polar bear? What method does he use to maximise or minimise thermal energy transfer?

© Oxford University Press 2011 IP1.7.5 Energy transfers 2 The polar bear has thick fur which minimises thermal energy transfer to its surroundings. It insulates the bear and keeps the heat close to its skin.

© Oxford University Press 2011 IP1.7.5 Energy transfers 2 Look at the list below. Which of these helps the human body maximise thermal energy transfer to its surroundings and which helps it to minimise thermal energy transfer. How does each process work?  Sweating  Hairs stand on end  Shivering  Reduced blood flow to the skin