Page 11 - Curriculum Visions Dynamic Book

Plants
Only living plants can make compounds of carbon. They use the energy of sunlight in a process called photosynthesis.
In photosynthesis, six molecules of carbon dioxide from the air combine with six molecules of water, forming one molecule of glucose (sugar), and releasing six molecules of oxygen back into the atmosphere.
Some sugar is combined with nitrogen compounds to form the proteins that make up tissues.
Sugar is also converted into larger, more complex molecules called starches and fats. These are forms of energy that can be stored
for later use.
Plants release carbon dioxide when they are burned (a rapid form of decay).
 The natural carbon cycle. Note that, in addition, over geologic time carbon is stored in rocks. It is released when fossil fuels are burned.
EQUATION: Photosynthesis
Carbon dioxide + water ➪ glucose + oxygen 6CO2(g) + 6H2O(l) ➪ C6H12O6(s) + 6O2(g)
fossil fuels: hydrocarbon compounds that have been formed from buried plant and animal remains. High pressures and temperatures lasting over millions of years are required. The fossil fuels are coal, oil and natural gas.
molecule: a group of two or more atoms held together by chemical bonds.
oxidation: a reaction in which the oxidising agent removes electrons.
photosynthesis: the process by which plants use the energy of the Sun to make the compounds they need for life. In photosynthesis, six molecules of carbon dioxide from the air combine with six molecules of water, forming one molecule of glucose (sugar) and releasing six molecules of oxygen back into the atmosphere.
Plants make sugars by photosynthesising sugars using carbon dioxide from the air.
As sugars are oxidised by plants for energy, carbon dioxide is released back into the air.
As sugars are oxidised by animals for energy, carbon dioxide is released back to the air.
Carbon-based chemicals are absorbed by animals as they consume plant matter.
The main source of carbon dioxide is the air.
➡ + Oxygen Carbon dioxide
Water
Organisms in the soil break down dead plant and animal tissue, and carbon dioxide gas is released as it decays.
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