• Carbon And Oxygen
• Oxygen And Carbon Dioxide
• Carbon And Oxygen Cycle Diagram
• Carbon And Oxygen Covalent Bond
• Carbon And Oxygen Bonding
• Carbon And Oxygen Cycle Diagram

Everyone is aware of the high carbon dioxide levels in the air and its contribution to global warming. And many of you have heard that plants can convert this CO2 into oxygen. Plants are important in controlling the CO2 level, but they don’t convert CO2 into O2.

Did you know that plants also take in oxygen and produce carbon dioxide, just like animals?

The oxygen cycle and the carbon cycle are closely related as they both involve photosynthesis and cellular respiration. Carbon dioxide is taken in by producers to undergo photosynthesis, and oxygen is released as a bi-product. Cellular respiration takes oxygen from the atmosphere and releases carbon dioxide. Carbon moves from one storage reservoir to another through a variety of mechanisms. For example, in the food chain, plants move carbon from the atmosphere into the biosphere through photosynthesis. They use energy from the sun to chemically combine carbon dioxide with hydrogen and oxygen from water to create sugar molecules.

All of this is a bit academic, but very interesting if you really want to understand plants. Datacard printers driver download.

Plants Don’t Produce Oxygen (O2) From Carbon Dioxide (CO2), Photo source: Science Sparks

Understanding Photosynthesis

All plants, including algae and cyanobacteria carry out photosynthesis. This is a process where CO2 and water are converted to sugars and oxygen. It takes place in special cell structures called chloroplasts which are small organs inside plant cells. Each one of these chloroplasts is a small chemical manufacturing plant that contains an important molecule called chlorophyll.

Chlorophyll is able to capture sunlight and turn it into useable chemical energy. This energy is then used to produce sugars from CO2 and water. Chlorophyll is a special molecule that is able to trap blue and red light, and reflect most of the green light. That is why plants look green.

Why is sugar so important? Sugar is the building block for making many of the more complex chemicals found in a plant. Drivers behringer sound cards & media devices. It is also the vital energy source to do everything that takes place in a plant.

Since photosynthesis requires light, it is only active during the day. Plants don’t use CO2 or make food energy in the dark.

Carbon And Oxygen

Is Carbon Dioxide Converted to Oxygen?

Much of the popular press describes photosynthesis in very simple terms and says that plants convert CO2 into O2. This simplification is incorrect.

The reaction that occurs is a two step process.

Step 1:

In step 1, light energy is captured by chlorophyll and used to break up water into free electrons, hydrogen ions (protons) and oxygen gas.

2H₂0 –> 4 e^– + 4 H⁺ + O₂

Most of this oxygen is then expelled from the plant, making it available to animals. The oxygen in the air and the oxygen which we breathe comes from water, not CO2.

Step 2:

Oxygen And Carbon Dioxide

Step 2 is actually a complex set of reactions called the Calvin Cycle which takes the electrons from step 1, combines it with CO2 to form sugars.

Plants Use Oxygen Just Like Animals

Most gardeners understand that plants produce O2. What many don’t know is that plants also use oxygen just like animals.

The sugars are an energy source for all living things. It takes energy to build larger molecules, like proteins and carbohydrates which are key building blocks for animals to grow. They get this energy through a process called respiration.

During respiration, oxygen is combined with sugar to produce energy, water and CO2. This reaction is also a multi-step process and occurs in animals and plants.

Carbon And Oxygen Cycle Diagram

When leaves respire they get the needed oxygen from one of two sources. Some is absorbed through the stomata of the leaves and some comes from photosynthesis.

In roots, the required oxygen comes mostly from the soil. This is why roots need a significant amount of air around them. When they are overwatered they can’t get enough oxygen and they die.

Green herbaceous stems have stomata and respiration can occur as in leaves. Woody stems have openings called lenticels which allow the movement of gases in and out of the plant.

lenticels on a birch tree

A key difference between respiration and photosynthesis is that the former occurs all of the time, day and night, while photosynthesis only occurs in light.

How Can Plants Add Oxygen to Earth?

I’ve just discussed two processes that go on in plants. One produces oxygen and the other uses it up. If that is true, why do plants add a net amount of oxygen to the air?

Photosynthesis produces about 10 times more oxygen than respiration consumes. On balance, plants are net producers of oxygen.

Anaerobic Respiration

Carbon And Oxygen Covalent Bond

The respiration discussed above is more correctly called aerobic respiration because it occurs in the presence of oxygen. There is a similar process that does not require oxygen, called anaerobic respiration. In this process sugars are converted to energy, alcohol and CO2.

This kind of respiration is used by yeast in a fermentation process, by anaerobic bacteria and it takes place in Bokashi. This process is less efficient in producing energy, but it does mean some organisms can live in low oxygen environments, like very heavy clay soil.

Earth has a surprising new player in the climate game: oxygen. Even though oxygen is not a heat-trapping greenhouse gas, its concentration in our atmosphere can affect how much sunlight reaches the ground, and new models suggest that effect has altered climate in the past.

Oxygen currently makes up about 21 percent of the gases in the planet’s atmosphere, but that level hasn’t been steady over Earth’s history. For the first couple of billion years, there was little oxygen in the atmosphere. Then, about 2.5 billion years ago, oxygen started getting added to the atmosphere by photosynthetic cyanobacteria. “Oxygen is produced as a waste product of photosynthesis. It is consumed through respiration,” explains University of Michigan climate scientist Chris Poulsen, lead author of the study published today in Science.

That waste product sparked a mass extinction known as the Great Oxygenation Event. But over time, new forms of life evolved that use or expel oxygen in respiration, and atmospheric oxygen levels continued to increase. “The production and burial of plant matter over long periods causes oxygen levels to rise,” explains Poulsen. Levels can fall again when that trapped ancient organic matter becomes exposed on land, and elements such as iron react with oxygen from the atmosphere, a reaction called oxidative weathering. As a result of these processes, atmospheric oxygen levels have varied from a low of 10 percent to a high of 35 percent over the last 540 million years or so. Palmsource input devices driver download for windows.

Poulsen and his colleagues were studying the climate and plants of the late Paleozoic, and during a meeting they started talking about whether oxygen levels might somehow have affected climate in the past. Studies have shown that atmospheric carbon dioxide has been the main climate driver through deep time, so most thought oxygen's role has been negligible.

But computer models based on carbon data have not been able to explain everything in the record. For example, the Cenomanian, an age in the late Cretaceous, was marked by high carbon dioxide and soaring temperatures, but models of this time usually spit out polar temperatures and precipitation rates that are too low when compared with data taken from the paleogeologic record. So Poulsen began modifying a climate model to test the oxygen idea, and the results showed that changes in oxygen concentration did indeed have an impact through a series of feedbacks.

“Reducing oxygen levels thins the atmosphere, allowing more sunlight to reach Earth’s surface,” explains Poulsen. More sunlight lets more moisture evaporate from the planet’s surface, which increases humidity. Because water vapor is a greenhouse gas, more heat gets trapped near Earth's surface, and temperatures rise. The increased humidity and temperature also leads to increases in precipitation. By contrast, when oxygen concentrations are higher, the atmosphere gets thicker and scatters more sunlight. As a result, there is less water vapor to trap heat.

Carbon And Oxygen Bonding

Adding in oxygen's affects during other time periods could lead to more accurate models of the planet’s past, the researchers say. But Poulsen cautions that the study has no affect on what is known about Earth’s current climate. The planet’s climate is changing today because levels of greenhouse gases such as carbon dioxide and methane are rising dramatically—oxygen isn’t a factor.

Carbon And Oxygen Cycle Diagram

“Oxygen levels are dropping today but at a very slow rate, approximately tens of parts per million per year,' he says. 'This rate is much too slow to affect climate in the modern world.” Give the planet another million years, though, and future climate scientists will need to add oxygen to their models to get the full picture.