Ecosystems 11

Year 10 Topic 2 – Learning Opportunity 11: The Carbon Cycle
This learning opportunity has 5 tasks to complete.
Target time: 50 minutes.

By the end of this learning opportunity you will be able to:
describe how different materials cycle through the abiotic and biotic components of an ecosystem
explain the importance of the carbon cycle, including the processes involved and the role of microorganisms as decomposers

Key words: carbon dioxide, combustion, photosynthesis, respiration, decomposition, fossil fuels, biotic, abiotic.

Task 1: Match the key processes to their definitions. Watch the video to help you.

Find the answers at the end of the blog.

Task 2: Use ‘look, cover, write, check’ to memorise this diagram of the carbon cycle.

Task 3: Answer these questions about the carbon cycle. Use a copy of the diagram to help.

Bronze
a) Which 3 processes add carbon dioxide to the air?
b) Which process removes carbon dioxide from the air?
c) Which living organisms remove carbon dioxide from the air?
d) How is carbon typically released from animals?
e) How is carbon transferred between organisms in an ecosystem?
Silver
f) What role do decomposers play in the carbon cycle?
g) How does the natural carbon cycle (not including combustion) usually keep the levels of carbon dioxide in the air fairly constant?
Gold
h) A large forest is cleared by burning. What effects will this have on the amount of carbon dioxide in the air immediately and over a longer period?
i) Why is planting trees recommended as a way of slowing down global warming?

Find the answers at the end of the blog.

Task 1: Answers

Task 3: Answers

a) Which 3 processes add carbon dioxide to the air? Combustion, respiration, decomposition
b) Which process removes carbon dioxide from the air? Photosynthesis
c) Which living organisms remove carbon dioxide from the air? Plants
d) How is carbon typically released from animals? Carbon is released as carbon dioxide during respiration.
e) How is carbon transferred between organisms in an ecosystem? Compounds containing carbon are passed up the food chain when animals eat plats and other animals.
f) What role do decomposers play in the carbon cycle? Decomposers respire using dead plant and animal matter, releasing carbon back into the air as carbon dioxide.
g) How does the natural carbon cycle (not including combustion) usually keep the levels of carbon dioxide in the air fairly constant? Levels of respiration and photosynthesis are quite equal, so similar amounts of carbon dioxide and taken in (through photosynthesis) as are released (by respiration).
h) A large forest is cleared by burning. What effects will this have on the amount of carbon dioxide in the air immediately and over a longer period? Large amounts of carbon dioxide will be released into the air immediately by combustion (burning). Over a longer period less carbon dioxide will be removed from the air than before because of less photosynthesis.
i) Why is planting trees recommended as a way of slowing down global warming? Trees remove carbon dioxide from the air during photosynthesis.

Task 4: Complete the quiz using the link below.

Quiz

You may need to refer to this diagram if it doesn’t appear in the quiz.


Challenge Task: Correct two mistakes in each statement. One mistake is in the science and one is with the SPaG (spelling, punctuation and grammar).

• Carbon dioxide is removed from the atmopshere by either
photosynthesis or respiration.
• Carbon dioxide can be returned to the atmosphere when animals and plants respire when fossil fuels are burned when other biomass is burned or when compounds are decayed by soil.
• Carbon becomes part of compounds in fats proteins and carbohydrates of plants and animals. It is passed through the food chain when organisms are consumed. Carbon is then passed back into the atmosphere when animals excrete or die.
• When fossil fuels such as Coal, Oil and Natural Gas are burnt, or when products made from animals or plants are burnt, the gases are released into the atmosphere. This process of burning substances is called consumption.

Challenge Task: Answers

The SPaG mistakes are corrected and explained in purple and corrections to the science are in red.
Carbon dioxide is removed from the atmosphere by
photosynthesis only. (Spelling corrected.)

Carbon dioxide can be returned to the atmosphere when animals and plants respire, when fossil fuels are burned, when other biomass is burned, or when compounds are decayed by decomposers. (Commas added.)

Carbon becomes part of compounds in fats, proteins and carbohydrates of plants and animals. It is passed through the food chain when organisms are consumed. Animals excrete or die and carbon is then passed back into the atmosphere when microorganisms respire. (Comma added.)

When fossil fuels such as coal, oil and natural gas are burnt, or when products made from animals or plants are burnt, the gases are released into the atmosphere. This process of burning substances is called combustion. (Removal of capital letters, coal, oil and natural gas are not proper nouns.)

End of Learning Opportunity 11