what is the carbon cycle? -...

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What is the Carbon Cycle? The Carbon Cycle is a complex series of processes through which all of the carbon atoms in the world are recycled. The same carbon atoms in your body today have been used in countless other molecules since time began. The wood burned just a few decades ago could have produced carbon dioxide which through photosynthesis became part of a plant. When you eat that plant, the same carbon from the wood which was burnt can become part of you. The carbon cycle is the great natural recycler of carbon atoms. Unfortunately, its importance is rarely stressed enough. Without the proper functioning of the carbon cycle, life as you know it would not exist. You and every other living thing on this planet are based upon carbonyou are a carbon-based life form. Without carbon you would not be alive. We believe that it's vital to understand how the carbon cycle works in order to see the danger of it not working. Therefore, let's look at a sample carbon cycle and explore how carbon atoms move through our natural world. Plants, animals, and soil interact to make up the basic cycles of nature. In the carbon cycle, plants, producersorganisms that make their own energyabsorb carbon dioxide from the atmosphere and use it, combined with water they get from the soil, to make the substances they need for growth. Photosynthesis is the process that plants use to take carbon dioxide (CO2 ) from the air and water from the soil to produce energy for themselves. The process of photosynthesis incorporates the carbon atoms from carbon dioxide into sugars. Animalswho are consumers since they must eat other organisms to get energysuch as rabbits, eat plants and use the carbon to build their own tissues through a process called respiration. Other animals, such as a fox, eat the rabbit and then use the carbon for their own needs, again through the process of respiration. These animals return carbon dioxide into the air when they breathe, and when they die, they return carbon to the soil as their bodies are decomposed by organisms such as fungi and bacteria. The fungi and bacteria are known as decomposers since they decomposebreakdownthe bodies of dead organisms. The carbon atoms returned to the soil may then be used in a new plant or small microorganisms. Ultimately, the same carbon atom can move through many organisms and even end in the same place where it began. Herein lies the fascination of the carbon cycle; the same atoms can be recycled for millenniamillions of years! When animals die, such at the dinosaurs did millions of years ago, their decomposing bodies put large amounts of carbon in the ground. As their bodies break down and return carbon to the Earth, the carbon is recycled in the form of fossil fuelsoil, gasoline, diesel, kerosene, natural gas, etc.that humans burn to produce energy. This burning of fossil fuels by humans to produce energy is called combustion.

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Page 1: What is the Carbon Cycle? - images.pcmac.orgimages.pcmac.org/SiSFiles/Schools/AL/MobileCounty/HankinsMiddle/... · What is the Carbon Cycle? The Carbon Cycle is a complex series of

What is the Carbon Cycle?

The Carbon Cycle is a complex series of processes through which all of the carbon atoms in

the world are recycled. The same carbon atoms in your body today have been used in countless

other molecules since time began. The wood burned just a few decades ago could have produced

carbon dioxide which through photosynthesis became part of a plant. When you eat that plant, the

same carbon from the wood which was burnt can become part of you. The carbon cycle is the great

natural recycler of carbon atoms. Unfortunately, its importance is rarely stressed enough. Without the

proper functioning of the carbon cycle, life as you know it would not exist. You and every other living

thing on this planet are based upon carbon—you are a carbon-based life form. Without carbon you

would not be alive. We believe that it's vital to understand how the carbon cycle works in order to see

the danger of it not working. Therefore, let's look at a sample carbon cycle and explore how carbon

atoms move through our natural world.

Plants, animals, and soil interact to make up the basic cycles of nature. In the carbon cycle,

plants, producers—organisms that make their own energy—absorb carbon dioxide from the

atmosphere and use it, combined with water they get from the soil, to make the substances they need

for growth. Photosynthesis is the process that plants use to take carbon dioxide (CO2 ) from the air

and water from the soil to produce energy for themselves. The process of photosynthesis

incorporates the carbon atoms from carbon dioxide into sugars. Animals—who are consumers since

they must eat other organisms to get energy—such as rabbits, eat plants and use the carbon to build

their own tissues through a process called respiration. Other animals, such as a fox, eat the rabbit

and then use the carbon for their own needs, again through the process of respiration. These animals

return carbon dioxide into the air when they breathe, and when they die, they return carbon to the soil

as their bodies are decomposed by organisms such as fungi and bacteria. The fungi and bacteria are

known as decomposers since they decompose—breakdown—the bodies of dead organisms. The

carbon atoms returned to the soil may then be used in a new plant or small microorganisms.

Ultimately, the same carbon atom can move through many organisms and even end in the same

place where it began. Herein lies the fascination of the carbon cycle; the same atoms can be recycled

for millennia—millions of years!

When animals die, such at the dinosaurs did millions of years ago, their decomposing bodies

put large amounts of carbon in the ground. As their bodies break down and return carbon to the

Earth, the carbon is recycled in the form of fossil fuels—oil, gasoline, diesel, kerosene, natural gas,

etc.—that humans burn to produce energy. This burning of fossil fuels by humans to produce energy

is called combustion.

Page 2: What is the Carbon Cycle? - images.pcmac.orgimages.pcmac.org/SiSFiles/Schools/AL/MobileCounty/HankinsMiddle/... · What is the Carbon Cycle? The Carbon Cycle is a complex series of

Answer the following questions using the information you have read: 1. Define photosynthesis. 2. Define respiration. 3. Define combustion. 4. Define decomposition. 5. Define decomposers. 6. Define producers. 7. Define consumers. 8. Give 2 examples of decomposers. 9. Give an example of a consumer.

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Page 3: What is the Carbon Cycle? - images.pcmac.orgimages.pcmac.org/SiSFiles/Schools/AL/MobileCounty/HankinsMiddle/... · What is the Carbon Cycle? The Carbon Cycle is a complex series of

10. Give an example of a producer. 11. Define fossil fuels. 12. List 3 examples of fossil fuels. 13. What gas do animals release to the atmosphere as they undergo respiration? 14. What gas do plants take from the atmosphere as they undergo photosynthesis? 15. What cycle is pictured above? 16. What is happening in the picture at number 5? 17. Identify the fox, rabbit, cow, and trees as a consumer, producer, or decomposer. 18. Where do fossil fuels come from? 19. What is the source of carbon in fossil fuels? 20. Where is the carbon in the carbon cycle eventually returning? (Hint: Look at where the arrows are

pointing.)

21. Think further: What is all of the carbon that is returned to the atmosphere as carbon dioxide doing to Earth?

Source: http://library.thinkquest.org/11226/why.htm and Mrs. Morris’ brain