1. The Carbon Cycle Lesson Objectives: Describe the movement of carbon in the carbon cycle Starter: Why is carbon important?

2. AQA Science © Nelson Thornes Ltd 2006 2 A 4000 year old corpse preserved in ice. Why hasn’t it decomposed?

3. Why is carbon important? Carbon is the main constituent of all living cells (biochemistry, organic chemistry) Carbon can form long chained-molecules which are the basis for fats, carbohydrates, nucleic acids (DNA and RNA) and proteins. Component of fuel (coal and gas) Use in nanotubes for computers

4. AQA Science © Nelson Thornes Ltd 2006 4

7. Respiration, burning and decay Excrement and death Decay (micro- organisms and bacteria) Respiration

8. The Carbon Cycle Plants take in CO 2 because they need carbon and oxygen to use in Through photosynthesis plants make and other substances e.g. protein When animals eat plants they use some of the carbon containing compounds to grow Some carbon-containing compounds are used to release energy by photosynthesis glucose (carbohydrate) respiration.

9. Q1Write out the word equation for photosynthesis. Q2Write out the word equation for respiration. Q3What is carbon used for by plants? Q4What happens to the carbon when plants are eaten by animals? Q5When plants and animals die their bodies decay. How is the carbon returned to the atmosphere?

10. Your task – drama time In groups of 3 – 4 you need to ‘act’ out the carbon cycle You can use mini white boards as props This will be peer marked – top groups get stickers and sweets One person to be nominated the narrator

11. AQA Science © Nelson Thornes Ltd 2006 11

12. The carbon cycle True or false?

13. AQA Science © Nelson Thornes Ltd 2006 13 Green plants use carbon dioxide in photosynthesis. True

14. AQA Science © Nelson Thornes Ltd 2006 14 Combustion removes carbon from the atmosphere False – combustion releases carbon dioxide gas

15. AQA Science © Nelson Thornes Ltd 2006 15 The largest store of carbon is the atmosphere False – more is found in marine organisms and limestone rock deposits

16. AQA Science © Nelson Thornes Ltd 2006 16 Respiration adds carbon dioxide to the atmosphere True

17. AQA Science © Nelson Thornes Ltd 2006 17 Respiration only occurs in animals False – both animals and plants respire

18. Decomposers remove carbon dioxide from the atmosphere False – they respire and release carbon dioxide

19. AQA Science © Nelson Thornes Ltd 2006 19 Fossil fuels represent a huge (but decreasing) store of carbon True

20. AQA Science © Nelson Thornes Ltd 2006 20 Increasing carbon dioxide may cause global cooling False – scientists think it will cause global warming

21. AQA Science © Nelson Thornes Ltd 2006 21 Energy is transferred from plants to animals to decomposers True

22. AQA Science © Nelson Thornes Ltd 2006 22 Respiration releases energy to the environment in the form of heat True

23. Key word bingo respiration photosynthesis decay burning potato combustion deforestation dissolved Light intensity trees chloroplasts glucose xylem leaf