Friday May 1, 2015

LT: I can describe the effects of the carbon cycle.

Instructions:

1.Read the following article

2. Take notes on the note-catcher, or directly into your science journals

3. Draw a carbon cycle diagram, using the information from your notes and this reading.

----------------------------------------------------------------------------------------------------------------------------------Introduction: The Carbon Cycle

Carbon (C) is the basis of life on Earth. Scientists consider 99.9% of all organisms on the planet to be carbon based life. Those organisms need carbon to survive. Whether the carbon is in the form of a sugar or carbon dioxide gas, we all need it. Unlike energy, carbon is continuously cycled and reused. The Earth only has a fixed amount of carbon. The carbon cycle is the ultimate form of recycling.

Step 1: Start With Plants

Plants are a good starting point when looking at the carbon cycle on Earth. Plants have a process called photosynthesis that enables them to take carbon dioxide out of the atmosphere and combine it with water. Using the energy of the Sun, plants make sugars and oxygen molecules. All of the non-photosynthetic creatures on the planet use the oxygen. Every creature on the planet uses the sugars and starches created by plants.

Step 2: Then Animals Eat The Plants

Animals are the non-photosynthetic creatures of the planet. They are not able to create their own food. Instead, they eat plants or other animals. The sugars and starches they eat are broken down by a process of metabolism. The results are energy for the creature, water, and carbon dioxide molecules. The carbon dioxide then returns to the atmosphere where the plants use it again.

Step 3: Who Eats The Animals?

There are also decomposers involved in the carbon cycle. They break down organic material such as dead animals, poop, or leaves. Decomposers are able to break down the chemical compounds inside the body. They also release carbon dioxide as well as methane.

Sometimes the decomposers don't break down organic material. There are great oil fields under the surface that are made of plants that did not decompose millions of years ago. There are also layers of rock made of millions of creatures who had shells. One day this carbon will return to the everyday carbon cycle, but geological processes are much slower than living processes.

Step 4: Oxygen Cycling

Oxygen (O) atoms cycle through the ecosystem and the biosphere the way other elements do (especially carbon). The Earth has a fixed supply of the element even though it can be found everywhere, including the atmosphere, the oceans, rocks, and all living organisms. While not all organisms need to breathe oxygen, there is definitely oxygen inside of every organism.

Step 5: Oxygen Rarely Alone

Oxygen is one of the major compounds found in the atmosphere of the Earth. You never find oxygen floating around as individual atoms. Oxygen is always with other elements. You may find an oxygen molecule that has two oxygen atoms. There are molecules with three oxygen atoms called ozone. You will also find oxygen bound in water molecules and carbon dioxide. That oxygen floats through the atmosphere until it comes down to Earth and starts one of many cycles.

Step 6: Dissolved In Water

There is a large amount of oxygen dissolved in the water of oceans, lakes, and streams. As water moves, the oxygen is forced into solution. The organisms that live in the water breathe that oxygen by filtering it out of solution the way we do with the air. Over millions of years oxygen has also become an integral element in our rocks and land. Oxygen bonds with silicon (silicates), iron, and carbon (carbonates) to form many of the compounds in rock. Creatures like lichen are able to break down the rocks over thousands of years and release nutrients into the soil.

Step 7: We Need Oxygen To Survive

Last are the organisms of the world. They use oxygen in many forms. Their role in the cycle begins with carbon dioxide in the atmosphere. Plants take in that carbon dioxide and combine it with water to create sugars and oxygen molecules. Animals breathe that oxygen and both plants and animals use the sugars for energy. Through the process of metabolism, the sugars are broken down into water and carbon dioxide. Then the cycle begins again.

Carbon Cycle Steps Outlined