Microbes are the foundation of life as they’re everywhere. They are in the air we breathe, in the food we eat, in the ground we walk on and even inside us. There are more microbes on a person’s hand than there are people on the entire earth.
Microorganisms are by dictionary definition ‘microscopic organisms’. They do many jobs in an extremely wide field. Without them the planet wouldn’t survive, as we know it. We couldn’t digest our food, neither of course could animals, plants couldn’t grow, rubbish and waste wouldn’t decay and there would be a lot less oxygen in the air we breathe. Many people believe they were the very start of life, the start of evolution, which in turn led to humans, you and me. Microorganisms can be split into different groups, each with their own characteristics and ‘jobs’. There are Bacteria, Fungi, Protozoan and Viruses (although some people believe that viruses are not alive.)
Bacteria are a simple one-cell organism, measuring on average from 0.3 to 2 microns (0.001mm) in diameter and can been seen through a microscope. They are classified as prokaryotes. Bacteria are amazing organisms, when most people think of bacteria they think of disease and contamination. In reality bacteria can cause human and animal disease but they are also extremely important because of their immense flexibility of modification, easy reproduction and rapid growth. Bacteria have been around for millions of years and some of the oldest fossils are of bacteria-like organisms. This indicates they were the foundation of life.
Some bacteria live symbiotically in the guts of humans and animals to help with digestion and to aid with the destruction of harmful organisms. They can produce some vitamins needed for the body. Bacteria are also very important to plants as they help to convert nitrogen into a usable form.
They play a vital role in recycling carbon and sulphur and other chemical basics. Bacteria help to decompose animal waste, dead organisms into chemical elements. Some bacteria will reverse this and turn chemical elements into a different form that can then be used by animals and plants. Various bacteria are involved in a chemical process called fermentation used to make alcohol beverages. Sewage treatment plants use bacteria to purify the water. They can also be used to make certain drugs such as human insulin. Bacteria are of major importance in helping with research. They reproduce quickly and are relatively simple in structure compared to other organisms. They have helped scientists to understand how certain characteristics are inherited. Bacteria put the flavour into yoghurt and the curdling of milk so it changes to cheese.
A different type of microorganism is fungus. They are eukaryotic organisms. They lack chlorophyll and vascular tissue. They can range from a single cell to a body mass of branched ‘filamentous hyphae’. There are 100,000 species of fungi. The many varieties include yeasts, moulds, smuts and mushrooms.
Fungi cannot produce food because they lack chlorophyll, so they absorb food from their surroundings. Fungi can be found living on the land and in the water, living on decaying material. Fungi helps in the process of decomposition that breaks down complex material into simple compounds, this replenishes the soil with nutrients in a form that can be used by plants. Fungi are used greatly in food and drink industries. Mushrooms and truffles are considered delicates and with the making of cheese, moulds are added to Roquefort and Camembert to ripen and provide them with a characteristic flavour. Yeast is used for two main jobs. It is used in the process of fermentation where it breaks down sugar into carbon dioxide and alcohol. This is used for alcoholic beverages. Yeast is also used in baking as it gives off carbon dioxide. This causes bread to rise from the carbohydrates. Some people also eat yeast for protein and vitamin B.
Moulds have been found to produce very important antibiotics, which weaken or kill bacteria and other organisms that can cause disease. Penicillin was the first and most important antibiotic, which was discovered in 1928 by Sir Alexander Fleming. It was from the mould Penicillium notatum that is one of several green moulds.
Protozoa’s are another type of microorganism. These are minute acellular of unicellular organisms usually nonphotosynthetic. These tiny organisms are very important to animals and humans. Protozoa’s are to a certain extent responsible for the chalk cliffs in Southern England. Millions live in the sea, where they are eaten by the sea life. A stony shell covers Protozoa’s called foraminifers. When these organisms die the shells fall to the seabed and contribute to the development of limestone.
Viruses are the smallest type of organism (ultramicroscopic organism). These organisms work by being engulfed by the host’s organism cells. It then replicates itself only within the cells of the living hosts. Many viruses are pathogenic.
Viruses are being researched in great depth. There have been ideas that one-day maybe instead of using insecticides, virologists are in search of ways to use viruses that kill insects on crops so improving the yields and reducing the present damage caused by insects. This would have a huge benefit in the countries where there are severe shortages of food. They may well have major environmental problems. Also because viruses are simple organisms they are used greatly by scientists in research for understanding cells functions and reproduction. This has already resulted in the understanding of DNA and genes, but in the future this knowledge could help us change cells or replace mutated genes with healthy genes with diseases we have answers for. In some areas of science it is already used.
Scientists produce vaccines and drugs from either dead or alive viruses. Many viruses are harmful or maybe fatal to humans and animals. This is why it is extremely important to create vaccines, as viruses have the capacity can wipe out massive numbers i.e. epidemics. There are two methods used, either killing the virus and then injecting it into the body, which causes the body to produce antibodies stored in memory cells, or virologists select mild harmless forms of the virus. These stimulate the body, but no visible harm is caused.
These are a few good microbes and their jobs.
In conclusion I can argue that, there are many microorganisms, which do us, harm, but there are also many, that we could not live without. They help inside and outside the body. Even the bad organisms have taught us much about life and what we are made up of. Without them we wouldn’t understand about how we and other life forms work. As we now understand many types of organisms, we can prevent them from affecting us through vaccines. Bacteria especially have been given a bad name because they can cause fatal diseases but we couldn’t live without some beneficial types. There are thousands of uses for them and I am sure there will be more, which we will find in the future.