What do you imagine when you think about bacteria? You’d be forgiven for thinking bacteria are tiny bugs that are all over the place and make you sick. What would you say if these little creatures don’t necessarily make you sick? That in fact you need them to survive? Let’s zoom in for a second and look at what is happening in the world under a microscope.
Did you know you need bacteria to survive?
Flashback to 3.5 billion years ago. The earth was covered with oceans that regularly reached the boiling point. There were no dinosaurs wandering about the planet yet, but there were bacteria. These little creatures are the oldest form of life on Earth, even before the gigantic quadrupeds occupied our planet.
Microbes are invisible to the naked eye, but that doesn’t mean they aren’t there. They are everywhere. They’re in the air we breathe, on the ground we walk, in the food we eat and even in and on our bodies.
Imagine: more microbes live on your two hands than there are people on Earth. An average of about 8 billion bacteria live on your hands. On and in your body you will find a hundred thousand billion of them.
The world of microbes is microscopic but at the same time enormous. It consists of bacteria, archaea, fungi and protists. You’ve probably already heard about bacteria and fungi, but what do they actually do?
Thank you, microbes
Let’s say mankind wouldn’t exist without microbes. Without them we wouldn’t be able to eat or breathe.
Did you know the air we breathe and more specifically the oxygen in the air was created millions of years ago by the activity of bacteria?
Bacteria take care of vital processes on Earth, they defend the body against disease and they help us digest our food. Without them the world as we know it wouldn’t exist. Humans would not survive. They, however, can survive perfectly well without us.
Useful bacteria and fungi
In the body
Our body is full of useful bacteria, which are either neutral or helpful. Bacteria in the digestive system for example assist in breaking down nutrients.
Useful bacteria also protect us from harmful bacteria. They will occupy places in our body so that pathogenic bacteria are not given the opportunity to attach.
Other useful bacteria even come to our rescue and attack invading pathogens.
There are also useful fungi in the body. They make sure that harmful fungi cannot cause inflammatory diseases.
Thanks to bacteria plants are able to grow, waste will degenerate and we have enough oxygen to breathe.
Bacteria and fungi that grow in the ground or on dead vegetable material play an important part in the composting process. They break down organic matter by digesting simple carbohydrates such as starch, sugars and proteins. During this decomposition process they use oxygen and residual gases, carbon dioxide, water and heat will develop. The result is compost.
Bacteria are also important players in the cycle of chemical elements such as carbon and nitrogen. Both elements are necessary for human life and are retrieved from the cellular material of all organisms. Indispensable molecules such as proteins and DNA contain it.
Trees, plants, algae and photosynthetic bacteria like cyanobacteria in the ocean convert carbon dioxide from the air. Aided by light as an energy source, oxygen is produced. Also complex hydrocarbons such as glucose are formed. This process is called photosynthesis. Only plants and some bacteria are suitable for this process because they contain a molecule with which solar energy can be captured, namely chlorophyll.
The nitrogen gas in the air is too complex for plants and animals to be used as a nutrient. Luckily there are specialised bacteria that can convert nitrogen from the air (to ammonium) so plants can absorb the substance. Soil bacteria (azotobacter) and cyanobacteria in the ocean take care of this intense work. We eat the plants and reap the benefits.
Bacteria are also to be found in the water cycle. Water is an important resource for human life.
Surface water such as seawater is evaporated into the atmosphere as clouds. Scientists have found evidence that the process by which clouds may be converted to rain is created to a large extent by bacteria. Once this rain falls onto Earth, it will drift back into waterways or it will subside as ground water. This ground water is pumped up out of the ground and we use it as drinking water.
Some bacteria can even purify polluted water. The microorganisms convert the dangerous substances into harmless.
Did you know that some food wouldn’t exist without the presence of bacteria? Bacteria assist in the fermentation of food, such as with yoghurt and salami. They convert carbohydrates like sugars into acids. This provides a characteristic taste and it also gives the food a longer storage life.
Finally, there are also foods to which probiotics or useful bacteria are added, to improve your health. These are usually dairy products or supplements in the form of powders or pills.
Surviving with microbes
Bacteria and fungi don’t just make you sick. For the amount of harmful microbes there are as many or even more useful microbes. Thanks to them, we can live on this planet. And if we are smart, we will use these little creatures to our advantage.