CARBON CYCLE
The listening activity has to be divided into two parts:
Part 1
A/ Word study. Match the words and their definitions
1. algae
a) the part of the world in which animals, plants etc. can live
2. autotroph
b) a very simple plant without stems or leaves that grows in or near water
3. cyanobacteria
c) bacteria that obtain their energy through photosynthesis
4. biosphere
d) organism that produces its own food from inorganic molecules
B/ Explain the difference between open and closed systems in biosphere.
Part 2
A/ Word study. Decide if the following statements are true or false.
Strike means to hit or fall against the surface of something.
T
F
Starch is a substance that is mixed with water and is used to soften cloth.
T
F
Rigid is an adjective describing someone who is willing to change their ideas or behaviour easily.
T
F
Sequester means to keep a person or a group of people away from other people.
T
F
Decompose means to decay or make something decay.
T
F
Saprobes are plants or organisms, that live on decaying
organisms.
T
F
Detritivores are heterotrophs that obtain nutrients by
consuming faeces.
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F
B/ The carbon cycle involves several chemical processes that are essential to life. Listen to the text
and summarize the main characteristics of the processes involved. Pictures with simple
descriptions may help you.
1. Energy in the sunlight
2. Green leaf
3. Carbon dioxide
4. Glucose
5. Starch and cellulose
6. Burning of a portion of a
tree.
7. Burning of fossils fuels.
8. Heterotrophs need to
consume other organisms.
9. The process of converting
glucose to energy.
10. Release of carbon dioxide into
the atmosphere – oxidative
respiration.
11. Animals release some
carbon as solid waste.
12. These solid waste
products are broken down by
decomposers.
13. Carbon circulates also in aquatic ecosystems.
14. bicarbonate ion
15. algae and aquatic plants
16. Carbon dioxide exchange between water and
atmosphere.