Explain carbon cycle with the help of a diagram. [5 MARKS]
Explain carbon cycle with the help of a diagram. [5 MARKS]
Drawing : 3 Marks
Explanation : 2 Marks
(i) Fixation of atmospheric Carbon dioxide:
Carbon is incorporated into life-forms through the basic process of photosynthesis which is performed in the presence of sunlight by all life-forms that contain chlorophyll. This process converts carbon dioxide from the atmosphere into glucose molecules. These glucose molecules are either converted into other substances or used to provide energy for the synthesis of other biologically important molecules.
(ii) Addition of carbon dioxide to atmosphere:
a. The utilization of glucose to provide energy to living things involves the process of respiration in which oxygen may or may not be used to convert glucose back into carbon dioxide. This carbon dioxide then goes back into the atmosphere.
b. Another process that adds to the carbon dioxide in the atmosphere is the process of combustion where fuels are burnt to provide energy for various needs like heating, cooking, transportation and industrial processes.
c. When organisms die the decomposition of their bodies recycles carbon dioxide back to atmosphere.
Drawing : 3 Marks
Explanation : 2 Marks
(i) Fixation of atmospheric Carbon dioxide:
Carbon is incorporated into life-forms through the basic process of photosynthesis which is performed in the presence of sunlight by all life-forms that contain chlorophyll. This process converts carbon dioxide from the atmosphere into glucose molecules. These glucose molecules are either converted into other substances or used to provide energy for the synthesis of other biologically important molecules.
(ii) Addition of carbon dioxide to atmosphere:
a. The utilization of glucose to provide energy to living things involves the process of respiration in which oxygen may or may not be used to convert glucose back into carbon dioxide. This carbon dioxide then goes back into the atmosphere.
b. Another process that adds to the carbon dioxide in the atmosphere is the process of combustion where fuels are burnt to provide energy for various needs like heating, cooking, transportation and industrial processes.
c. When organisms die the decomposition of their bodies recycles carbon dioxide back to atmosphere.
