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Unusual Microbial Activities

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Microbes: An Introduction

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All of you must have been sick at one point in your life. But do you know how we got sick? Or what is the causing factor? The most important cause of being sick is microbes. These are known to cause various diseases in humans, plants, and animals. But are all microbes harmful? Or are there some beneficial microbes too?

Not all microbes are harmful, some microbes are beneficial for us and help in day-to-day life in various fields of life. Some microbes also show very unusual activity. Such as light coming from wounds and spontaneous combustion in the forest.

To know more about microbes continue reading this article!

What Are Microbes?

Microbes are microscopic organisms that live in the air, water, and soil and can thrive in adverse conditions such as hot thermal springs, snow, and saline conditions. These organisms are not visible to the naked eye. Most microbes are beneficial for us but some are also harmful.

What is Microbial Activity?

There are various types of microbial activities such as aerobic, anaerobic, and fungal. The aerobic microbial activity requires oxygen whereas anaerobic microbial activity does not require oxygen.

Beneficial Functions of Microorganism

There are beneficial functions performed by microorganisms. Some of the functions are given below:

  • Production of Oxygen - There are various bacteria such as blue-green algae which produce oxygen.

  • Decomposition - Microbes help in the degradation of raw material, and also waste

  • Cheese and Yogurt - Bacteria ferment milk into cheese and yogurt.

  • Bread and Dough Production - Bacteria and fungi both ferment and produce bread and dough.

  • Alcohol Production - Bacteria ferment and produce alcohol and carbon dioxide.

Harmful Effects of Microorganism

Microorganisms can cause various diseases in animals as well as in plants.

They can cause very severe diseases and lead to deaths. Diseases caused by microbes are tuberculosis, aids, the common cold, etc. They can also reduce the crop yield, by causing various infections in plants.

They are also responsible for spoiling the food.

What is Unusual Microbial Activity?

Unusual activities which microbes do not perform usually. There are various unusual activities performed by microbes. Some of the unusual activities are given below:

Examples of Unusual Microbial Activity

Glowing Wound - There is a bacteria named Photorhabdus luminescens, that degrades the other bacteria in the human wound and gives yellowish-greenish color. These bacteria decrease the chances of more infections and also increase the recovery rate.

In 1862 there was a battle in America, and there were many wounded soldiers in this battle. After the battle when these soldiers lay down on the soil for rescue, soldiers noticed a greenish light coming from the wound. At that time they did not understand the logic of this bright light coming from the wound and called it an Angels glow. But after 139 year's scientists conducted various types of research and found out that this is because of a particular type of bacteria. This bacterium P. luminescens resides in a particular nematode. When these nematodes enter the wound of soldiers, they regurgitate the bacteria, which then consume other deadly microbes. This action gave off a greenish color.

Spontaneous Combustion - Forest fire is considered one of the natural calamities. There may be many reasons for spontaneous combustion, but one of the main reasons may be microbial action.

The microbes which are present under the soil or hay may produce a lot of heat, and this may raise the temperature and eventually may cause a fire. Now if there is more moisture content in leaves and other things, this will absorb more oxygen and hence will lead to more dangerous fires.

Interesting Facts

  • All the bacteria which are present in our body can weigh up to 4 pounds

  • There are more bacteria in a mouth of a person than the whole population of the world

  • Bacteria are the oldest microorganism in the world

  • There are more than 200 fungi in our foot

  • Fungi help plants to communicate with each other

Important Questions

1. Which type of microorganism is unusual?

Ans: Extremophiles are the most unusual types of microorganisms found in the most extreme environment. Archaeons especially live in the most unusual conditions.

2. What factors affect microbial activity?

Ans: Various factors affect microbial activity. Some of the factors are oxygen level, ph level, warmth, and moisture. These factors may increase or decrease microbial activity.

3. What are the four types of microbes?

Ans: There are various types of microbes. The most important are bacteria, viruses, fungi, protozoa, prions, viroids, worms, etc.

Key Features

  • In this article, we have read about microbes and their usual as well as unusual activity

  • Microbes are microscopic organisms found almost everywhere. These organisms can thrive in very adverse conditions too.

  • There are various functions performed by microbes. These functions may be beneficial or harmful for humans.

  • Some of the beneficial functions are oxygen production, and the formation of various products through the process of fermentation such as yogurt, cheese, etc.

  • The harmful effects of microorganisms are that they can cause various diseases in humans as well as plants. They can cause very severe and fatal diseases in humans and also reduce yield by causing various diseases in plants.

Practice Questions

  1. What is the most interesting microbe?

  2. What are the harmful activities of microbes?

  3. What does microbial mean?

  4. Do all microbes cause disease?

  5. What are the names of harmful microorganisms?

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FAQs on Unusual Microbial Activities

1. What is the effect of harmful effects of microorganisms on the human body?

Microorganisms cause various types of infectious diseases in humans. Some of the examples of diseases caused by microbes are given below: 

  • Tuberculosis - is caused by bacteria called mycobacterium tuberculosis.

  • AIDS - is caused by a virus called a retrovirus. It is a fatal disease.

  • Pneumonia - is caused by various bacteria and viruses. The most important causative agent is klebsiella 

  • Intestinal Diseases - Most intestinal diseases are caused by e.coli and other bacteria 

  • Food poisoning is also a very common disease caused by bacteria.

2. Write some factors affecting the growth of microbes.

There are various physical and chemical various affecting the growth of microbes:


Physical factors include PH, temperature, radiation, and pressure.


Chemical factors include nitrogen, oxygen, carbon, sulfur, phosphorus, etc. 


Optimum conditions of growth of microbes vary according to the variety of microbes. For most of the microbes, favorable conditions for growth are around 37°C.

3. What is the role of microorganisms in soil fertility and crop production?

Microorganisms are also known as farmers' friends. Because they enrich the quality of soil which is suitable for microbial growth. Bacteria and fungi break down the soil and minerals and convert them to absorbable forms. Nitrogen is one of the most important requirements of plants. But plants can't directly take nitrogen from the air, so they convert nitrogen into a suitable absorbable form.


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