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Air – Oxygen

Air is the most important thing that living things need. Try holding your breath for a while! Most people can only hold their breath for 1 to 2 minutes. The world record is an amazing 22 minutes, achieved by German free diver Tom Sietas. This can be compared to at most 7 days without water. Our need for air is absolutely extraordinary! Although many people assume that “air” and “oxygen” are the same, they are actually not.

Image of scuba divers diving in a coral reef using air (oxygen) to breathe.

Even professional divers use oxygen tasks to go underwater!

Air composition

Air is made up of a lot of different parts. By percentage, on Earth it is 78% nitrogen, 21% oxygen, and 0.93% argon. The main other parts of air are greenhouse gases like carbon dioxide, methane, and water vapor.

Even though the air around us is mostly nitrogen, most living organisms don’t actually need it. When we breathe in nitrogen, we don’t use it for anything, we just breathe it out. The same thing goes for argon. The two main components of air that are important to the body are oxygen and carbon dioxide. We can’t live without one, but will die if we have too much of the other. Can you guess which is which?

There is no air in outer space! This is why astronauts always need suits and air tanks to do their job.

There is no air in outer space! This is why astronauts always need suits and air tanks to do their job.

Respiration

Respiration is one of the most necessary processes of living organisms. Our bodies have a whole respiratory system to make sure we survive! During respiration, we first intake oxygen into our bloodstream. Then we release carbon dioxide back into the environment. The cells in our bodies all need oxygen to survive, which is why oxygen is so important to us. Carbon dioxide, differently, is harmful. This is why we the air we breathe in has more oxygen and less carbon dioxide than we breathe out.

Here’s a useful video for the process of respiration:

 

Different living organisms get air in different ways. Humans and most mammals use their lungs to breathe. Fish and plants also need oxygen, but they have adapted to their environments. Both groups go through respiration in different ways. Fish, for instance, have gills which they can use to get oxygen dissolved in water. Plants, contrarily, take in oxygen through tiny holes in their leaves called stomata.

Stomata in plant leaves

Stomata in plant leaves

Photosynthesis

Air is important to plants in another way: without it, plants can’t make food! If humans and animals can eat foods high in glucose, plants have to make their own. Plants do this through a process known as photosynthesis.

How photosynthesis works

How photosynthesis works

Photosynthesis is important both for plants and for the whole environment! If plants didn’t convert carbon dioxide into oxygen, we wouldn’t be able to breathe and live. This is why deforestation, or cutting down forests, is bad for the environment. By cutting down trees, we are reducing the amount of oxygen available for us in the air!

Cutting down trees gives us more trees. But it is also very dangerous for the environment!

Cutting down trees gives us more trees. But it is also very dangerous for the environment!

Harming our environment

Air Pollution

The invention of many technologies has improved our lives in a lot of different ways. Yet, in the process, technology has also harmed our environment. One of the things that has been getting worse on Earth is air pollution. Huge amounts of toxic gases are released into the environment every day. These gases come from car engines and furnaces in electric and manufacturing plants. This makes it both hard to breathe and has consequences for a lot of other life forms!

Air pollution has gotten very bad in the last couple of years. Parts of the world no longer see clear blue skies!

Air pollution has gotten very bad in the last couple of years. Parts of the world no longer see clear blue skies!

Global Warming

Another bad thing that happened from our overuse of technology is global warming. Burning petrol or fossil fuels releases a lot of carbon dioxide and water vapor into the air. The amount of methane is increased by large cattle farms. All these are greenhouse gases. Greenhouse gases trap sunlight inside the atmosphere and make the Earth hotter. The increase in greenhouse gases has led to what we now call global warming.

Greenhouse gases have the same effect as the glass panels in normal greenhouses. They trap sunlight and heat and increase the temperature inside.

Greenhouse gases have the same effect as the glass panels in normal greenhouses. They trap sunlight and heat and increase the temperature inside.

Global warming has a lot of bad effects. One of them is rising sea levels. Warmer temperatures melt the ice at the North and South poles. This releases the water trapped in icebergs into our oceans. This makes the seas rise higher and threatens to flood the cities that are closer to the sea level! We are also experiencing more droughts and heat waves. A lot of animals, like polar bears, are being endangered by global warming.

Now you are aware of these dangerous climate effects! There are a lot of ways you can help reduce air pollution and global warming. Even small things, like turning off your electrical devices when you’re not using them, can help a lot! Using less cars and more public transport can also help decrease the amount of harmful gases in the air!

Other Resources:

https://climatekids.nasa.gov/10-things-air/

https://kids.britannica.com/kids/article/respiration/400163

https://eschooltoday.com/pollution/air-pollution/what-is-air-pollution.html

Climate Basics for Kids

Written by: Minh Nugeyn