While both photosynthesis and cellular respiration provide energy for life, there is a general ratio that needs to be kept between the two in order for the environment to remain stable. Basically, there should always be more - or an equal amount of - photosynthesis occurring than cellular respiration. An increase in the amount of cellular respiration (likewise, a decrease in photosynthesis) could lead to what is known as global warming.

Global warming is the increase of the Earth's surface temperature. This occurs due to the greenhouse effect, which happens in earth's atmosphere.

The greenhouse effect is the warming of the atmosphere caused by CO2 (carbon dioxide), CH4 (methane gas), and other gases that absorb infrared radiation and slow its escape from the atmosphere of Earth.

Photosynthesis and Global Warming

Carbon Cycle

Carbon dioxide is an important gas that plays a huge part in the greenhouse effect. CO2 is raw material for photosynthesis, and a waste product for cellular respiration. Together, cellular respiration and photosynthesis keep carbon cycling from organic and inorganic compounds on a global scale. Photosynthesis absorbs over a billion tons of carbon dio-
external image carbon-dioxide.jpg
xide a year, and most of the carbon is returned to the Earth's atmosphere by cellular respiration, decomposition, and the burning of fossil fuels. Since the Industrial Revolution, the output of carbon dioxide gas into the atmosphere has steadily increased over the years. An increase concentration of greenhouse gases such as carbon dioxide has lead to global warming.

Fossil Fuel

Over the years, the discovery of coal and other fossil fuels have lead to an increase in the world of industry- but they have also lead to global warming. When fossil fuel is burned, it releases energy and CO2. The energy is harnessed to do work, such as run factories, convert electricity, power cars, and people's homes. The carbon dioxide however is released into the atmosphere, where it adds to the CO2 levels and the greenhouse effect. This can be combated with photosynthesis from plants, seeing as photosynthesis uses carbon dioxide gas to create oxygen gas, keeping the ratio of carbon dioxide and oxygen even. This would slow down the greenhouse effect as it would eliminate some carbon dioxide. However, the rain forests and other large sources of green plants are being cut down, and there is an imbalance of carbon dioxide gas and oxygen gas. This also aids global warming and the greenhouse effect. By stopping the decimation of rain forests and switching to greener, more earth friendly energy, global warming can be slowed down.

CO2 Emission Rate

Along with the increase in use of fossil fuels, the increase of CO2 emission has gone up; or rather, CO2 is the direct product of burning fossil fuels. In an ideal setting, any amount of CO2 emission would be fine, as long as there was an equal occurrence of photosynthesis going on. However, when forests are chopped down, not only is a high amount of CO2 entering the atmosphere (from the burning of fossil fuels) but the oxygen created from the photosynthesis occurring in the forest is decreasing. The ratio becomes unbalanced, and the air becomes polluted.

Cellular Respiration and Global Warming

Cellular Respiration and Carbon Dioxide

Cellular Respiration converts oxygen, which is obtained from the atmosphere, into carbon dioxide (CO2) , which is released into the atmosphere. Cellular respiration is done by all cells- besides humans and animals, plants, specific bacteria and algae also go through cellular respiration. However, only plants, algae and the specific bacteria go through the process of photosynthesis. The carbon dioxide and oxygen ratio is balanced in these three types of cells, because of they all go through the process of photosynthesis and cellular respiration. Since animals and humans do not go through photosynthesis, more carbon dioxide is being released than consumed in photosynthesis. This causes an excessive amount of carbon dioxide in Earth's atmosphere.

Carbon dioxide is created and released as a waste product during the Kreb's Cycle of cellular respiration. Carbon dioxide is also released before beginning the Kreb's Cycle. Every living cell does cellular respiration, so every living cell also releases carbon dioxide into the atmosphere. This means that cellular respiration adds to the greenhouse effect, which in turn aids global warming by increasing the temperature of Earth. This is killing many animals and creatures that live in cold climates, such as the Harp Seal, and the Polar Bear. By balancing the amount of oxygen, carbon dioxide and other gases involved in global warming, we can preserve the lives of these creatures and keep the temperature of our earth down.



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Rowell, Andy. (2010). World CO2 at Record Levels. Retrieved November 28th, 2010, from