XXVI. Retell the text using this picture

XXV. Now read the following passage about the carbon and oxygen cycle.

The movement of carbon dioxide and oxygen through an ecosystem is called the carbon and oxygen cycle. In this passage, we will focus on the cycle of carbon dioxide. There are two ways that carbon dioxide is removed from the atmosphere. The first is through the ocean, which is like a huge reservoir that absorbs much of the gas. The second way is by plants that take in carbon dioxide through the process of photosynthesis.

In a natural system, carbon dioxide is released back into the atmosphere through respiration when an animal, such as a deer, breaks down food and energy is released. Carbon dioxide is also put back into the atmosphere through a process called decomposition. This process occurs when dead plants and animals are broken down by the actions of bacteria.

Human activity, however, has seriously affected this cycle by releasing more carbon dioxide into the atmosphere than is taken away. This extra carbon dioxide is released into the atmosphere in two ways. The first is through the burning of fossil fuels, such as coal, oil, and gas. The second is through deforestation, where trees are either cut or burned, releasing all the stored carbon dioxide into the air.

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