Sci-ber Text - 9th Grade

Atmosphere - What Cool Title Goes Here?

This diagram above looks a lot like a food chain, right? You could think of the arrows showing the direction of energy, but let's think of it another way...

If the arrows show the direction of carbon atoms, what would you call the diagram now? What should the title of the page be?

If you said The Carbon Cycle, then you are on the right track. If you came up with something more creative, then you are doing better than I amtoday! Let's take a look at how carbon gets from one place to another, and the form by which it travels.

Carbon dioxide (CO₂) is the major source of carbon in the atmosphere. 99.6% of the carbon in the atmosphere is in this form. Plants take in CO₂ during the process of photosynthesis, along with water vapor, to form oxygen and glucose. Glucose, a sugar, is an organic molecule, which means it contains carbon.

Animals eat plants for energy, and in the process the carbon atoms in the glucose get converted into another form during the process of respiration. Glucose and oxygen react to produce carbon dioxide which is released back into the atmosphere. Carbon is also incorporated into many of the different molecules needed by living things to grow, repair, and reproduce.

Once an organisms dies, what happens to the collection of the countless atoms that make up the body? What happens to the carbon atoms in particular? Decomposers break down the complex molecules into simpler substances. Carbon dioxide is again released into the atmosphere, where the carbon cycle can start over again.

Analysis:
Let's see if you can remember the main ideas of this page. Identify what form or process each box is referring to, and click on the box to check your understanding.

		Atmosphere stores carbon in
	is captured by plants by		release carbon in
Plants store carbon in				Decomposers store carbon in
	is taken in by animals by		is taken in by decomposers by
		Animals store carbon in