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Harmful Microorganisms

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IVSAT 2024

Technically a microorganism or microbe is an organism that is microscopic.  Microbiology is the study of Microorganisms. Microorganisms are divided into seven kinds: microorganism, archaea, protozoa, algae, fungi, viruses, and multicellular animal parasites every kind has a cellular composition, morphology, manner of locomotion, and replication. Microorganisms are beneficial in generating oxygen, decomposing organic material, presenting vitamins for flora, and retaining human health, however a few can be pathogenic and motive diseases in flora and humans.

Micro Organism

bacteria are unicellular organisms. The cells are defined as prokaryotic due to the fact they lack a nucleus. They exist in four important shapes: bacillus (rod form), coccus (round form), spirilla (spiral form), and vibrio (curved form). Most bacteria have a peptidoglycan cellular wall; they divide by binary fission; and they may own flagella for motility. The difference of their cell wall shape is a chief feature used in classifying those organisms. According to the way they reap electricity, bacteria are categorised as heterotrophs or autotrophs. Autotrophs make their own food through the usage of the energy of sunlight or chemical reactions, wherein case they may be referred to as chemoautotrophs. Heterotrophs obtain their energy by ingesting other organisms. Microorganisms that use decaying existence forms as a supply of strength are referred to as saprophytes.

Microscopic organisms, usually known as Microorganisms or microbes, are discovered all around us and also inside human bodies. 'Microorganisms' are present in living organisms like parasites, infections, algae, bacteria, and protozoa. Some of the Microorganisms like bacteria and fungi are commonly known but others like archaea are not well known.

Some Microorganisms like bacteria, are parasitic and can have a negative effect on plants, humans or animals by attacking the very cells that contain more complex living organism. They prey and feed on other beneficial Microorganisms and bacteria in the form of a disease that the plant or body must fight off through their immune system.

Microorganisms are the small living creatures that eat leaves, bark and trees. They are the reason behind the process of decomposition. Some of the Microorganisms feed on Harmful insects or on bacteria that might infect a plant. For instance, yeast is an example of useful microorganism.

The substances that remain after the process of decomposition are the byproducts of Microorganisms. These left out substances provides nutrients to the soil.

Although, some Microorganisms specifically bacteria can have a negative impact on the plants, animals or on human bodies by attacking the cells in a body which has more complex living organisms. They feed on the other good quality Microorganisms in the form of diseases which our body’s immune system has to fight through.

Microorganisms have a simple job in the different biological cycles, just as being a very important part of plant and soil biological systems. They divide the extinct plants and organism tissues and make some changes to help the plant to improve. There are almost 10 million Microorganisms in each gram of soil.

Microorganisms affect both animals and the human body from inside. Microscopic organisms, for instance, have an important job of processing and integrating the nutrient K and digest certain supplements. Additionally, they also help to convert acids into digestive organs. Some of the Microorganisms help to fight against the other Harmful Microorganisms that attack the digestive systems of the body. Microorganisms typically found in organisms and human bodies are known as "bacteria."

In spite of the fact that Anton van Leeuwenhoek originally watched microscopic organisms in the late 1600s, it was not until late in the nineteenth century that the germ hypothesis of sickness turned out to be commonly acknowledged. The exploration of French researcher Louis Pasteur gave powerful proof that specific Microorganisms were in charge of human disease. Among his different discoveries, he found three microscopic organisms, Staphylococcus, Streptococcus and Pneumococcus, that can cause disease in the human body.


Division of Microorganism


Archaea may be round, rod, spiral, lobed, square or abnormal in form. An unusual flat, rectangular-formed species that lives in salty swimming pools has also been found. Some exist as unmarried cells, others form filaments or clusters. Till the Seventies this group of microbes changed into categorised as bacteria. Many archaea were found residing in excessive environments, as an example at excessive pressures, salt concentrations or temperatures. Those kinds of organisms are called extremophiles.


Fungi may be single celled or very complicated multicellular organisms. they're found in pretty much any habitat; however most live on land, specially in soil or on plant cloth as opposed to in sea or freshwater. A group known as the decomposers develop in the soil or on useless plants wherein they play an important role inside the cycling of carbon and other factors. A few are parasites of plants causing diseases including mildews, rusts, scabs or canker. In vegetation, fungal diseases can lead to tremendous economic loss for the farmer. a totally small number of Fungi-motor illnesses in animals. In humans these include pores and skin diseases together with athletes’ foot, ringworm and thrush.


Protozoa is an informal time period for a collection of single-celled eukaryotes, both loose-living or parasitic, that feed on organic matter consisting of different Microorganisms or organic tissues and debris. Historically, protozoans were seen as "one-celled animals", because they regularly have animal-like behaviours, which include motility and predation, and lack a cell wall, as discovered in flowers and many algae.

All Protozoans are eukaryotes and consequently have a “proper,” or membrane-certain, nucleus. 


Algae are a numerous group of aquatic organisms that have the ability to conduct photosynthesis. positive Algae are acquainted to the majority; for instance, seaweeds (which includes kelp or phytoplankton), pond scum or the algal blooms in lakes. However, there exists a substantial and varied world of Algae that aren't simply useful to us, but are essential to our lifestyles.

As a well known rule, Algae are capable of photosynthesis and bring their private nourishment by using the usage of light energy from the solar and carbon dioxide, a good manner to generate carbohydrates and oxygen. In special words, maximum Algae are autotrophs or extra in particular, photoautotrophs (reflecting their use of moderate power to generate nutrients).

Algae are capable of reproducing thru asexual or vegetative techniques and via sexual replica.


Bacteria: They are the most common type of Microorganisms. They do not have a core inside the body and also do not contain organelles. Inside Microorganisms, there are two parts, Positive microbes which have thicker cell divider and Negatives which have a slimmer layer sandwiched between an internal and external film.

Microorganisms are very different and as far as the numbers are concerned they are present in a wide range on the Earth's surface.

Bacteria, of all the 'living' Microorganisms, cause the most illness issues in people, in spite of just generally a couple of microbes being hazardous.

Viruses are considered non-living creatures by many specialists. They basically comprise of nucleic corrosive (DNA or RNA,) and a protein coat. A Virus (an infection molecule) requires a host cell to reproduce. Inside the human life systems, an infection enters a human cell and captures it, and then utilizing the cell to reproduce.

These viruses are harmful and if they enter a human body, they might cause a serious health problem which it would take a long time to be cured or can be a disease which is not curable. HIV is a great example of a virus in the human body which leads to death.

Harmful Microorganisms

The majority of the infections are brought about by specific Microorganisms. These organisms are called pathogens. They are exceptionally adjusted to contaminate and duplicate inside a host. A few diseases brought about by pathogens are polio, cholera, mumps, rabies, jungle fever and so on.

A few Microorganisms need a transporter to send diseases. Here, Anopheles mosquitoes are the bearers used by the protozoan Plasmodium vivax to send the diseases to the host. Once inside the host, the Plasmodium begins destroying the red platelets. This causes different consequences, such as sickliness and hypoxia.

Different organisms directly enter the body through spoilt food, water, air or even only a little cut on your skin. The microbes, Streptococcus can enter your skin through an open injury. In any case, this microscopic organism is found in the vast majority’s throat and is moderately safe. Yet, once in a while, the contamination can be severe to the point that it can begin eating living creature and tissue. That is the reason it's likewise called "Substance eating microbes" or "Necrotizing fasciitis."

The greater part of the pathogenic sicknesses is transferable and irresistible. When pathogens enter the host body, they use the host supplements; additionally, attack the safe solutions of the host. This encouraged the invention of immunizations and anti-infection agents.

Microorganisms are attached to their host. A few sicknesses influence just creatures like Anthrax yet they can be transmitted to human too. A few diseases like crown nerve sickness taint plants by specific Microorganisms and infections. The infections influencing creatures and plants can diminish the quality and yield of the item and may also cause unfortunate death. In this way, it is important to control microbial development.

The destructive Microorganisms harm human body as well as the food we eat. Most of the time, it grows on our food and discharges dangerous items which can cause great harm. To avoid Harmful diseases, food conservation is done in different ways like purification, boiling, and filtration.

A couple of hurtful organisms, for instance under 1% of Microorganisms, can attack our body (the host) and make us sick. Microorganisms cause irresistible diseases, such as influenza and measles.

There is likewise solid proof that organisms may add too many Non– irresistible endless infections, such as a few types of malignancy and coronary illness. Diverse infections are brought about by various sorts of smaller scale living organisms.

It is Important to Recall That:

  • A pathogen is a small sized microorganism that can possibly cause illness.

  • Contamination is the attack and increase of pathogenic organisms in a person or a plant.

  • The disease is the point at which the contamination starts affecting the person’s immune system.

  • Contamination does not generally result in sickness!

  • To cause disease, Microorganisms must enter our bodies. The site at which they enter is known as the gateway of a section.

  • Microorganisms can enter the body through the four parts recorded beneath:

  • Respiratory tract (mouth and nose) such as flu infection which causes this season's flu virus

  • Gastrointestinal tract (mouth oral depression) for example Vibrio cholera which causes cholera.

  • Breaks in the skin surface, for example, Clostridium tetani which cause lockjaw.

  • To make us sick, organisms to need to:

  • Reach their aim site in the body

  • Attach to the goal site they are attempting to taint with the goal that they are not unstuck

  • Multiply quickly

  • Get their supplements from the host

  • Avoid and endure assault by the host's resistant framework


Uses of Microorganisms

1. Creation of Dairy Items:

Microbes are the key players here. Microscopic organisms help in evolution which helps in making diverse types of dairy items from milk like curd, buttermilk, spread, cheddar. Streptococcus is the most widely recognized variety of microbes that are utilized in the business generation of this item.

2. Bread Baking:

Types of Streptococcus are added to the batter before making bread to make the required flour.

3. Alcoholic Drinks:

Alcoholic beverages are arranged or produced by the procedure of maturation. Each beverage is made from a different form of items such as potato and grapes. At that point, it is aged, refined and liquor is made. Some even use bacteria and fungi. Mixed beverages incorporate wine, rum, vodka and so on.

4. Natural Acids:

Acetobacter, Rhizopus, Penicillium are several organisms that are used to age substrates, for example, nourishments developed from the beginning syrups. Some of the acids that are resolved and made on an extensive scale using parasites are acidic destructive, citrus remove, gluconic destructive, fumaric destructive and lactic destructive.

5. Enzymes:

Numerous Microorganisms are utilised in the induction of chemicals, such as lipase, lactase, protease, peptidase.

6. Steroid Creation:

Some bacterial and contagious species are utilised in the making of steroids that are then infused into the human body for various purposes.

7. Help in Sewage Treatment:

In addition to the fact that Microorganisms are useful to our body, they are additionally useful to nature. They help in the treatment of sewage.

8. Used as Insecticides:

Certain bacterial and contagious species are utilised to repel certain bugs and irritations from yields.

9. Production of Nutrients:

A fundamental nutrient that people need for proper assimilation is Vitamin B 12. Parasites are in charge of the making of B12.

10. Fertility of Soil:

Microorganisms have an essential job in keeping up the clearing of the dirt. They help in the fertilizing the soil. Additionally, Microorganisms present in the dirt help circulate air through it and improve the dirt with nitrates and different supplements. These supplements are required by the yields for a plentiful group.

Useful Microorganisms

  • Use to extract curd from milk.

  • Rhizobium found in pulse plants’ roots restores nitrogen from the air and delivers nitrogen compounds to the heart beat.

  • Micro-organisms also are utilised in winemaking, baking, pickling, and different meals-making procedures.

  • Alcoholic fermentation by yeast is widely used inside the preparation of wine and bread.

  • Microbes are used to reduce pollutants. For example, decomposers consisting of microorganism and fungi spoil our bodies and excreta to form inorganic compounds, which vegetation can absorb.

  • Microbes additionally play a vital function in the preparation of drug treatments. Antibiotics are chemicals produced by way of Microorganisms to kill microorganism. 

  • Penicillin is an antibiotic which is obtained from Penicillium.

  • The micro organism in our intestine helps in proper digestion and releases nutrition B, absorbed by the intestine.

  • Many vaccines are prepared from Microorganisms. These vaccines are given to youngsters to guard them from the disorder.

  • Positive microbes also are used inside the organic remedy of sewage and industrial effluents.

  • Yeast is utilised in making idli, bhaturas, bread, pastries, and cakes.

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FAQs on Harmful Microorganisms

1. What are harmful microorganisms?

Bacteria that cause disease also affect the water level. Bacteria are single-celled organisms that cannot be seen with the naked eye without a microscope. A few species of microorganisms are highly harmful microorganisms. They usually enter the water while unwashed faeces are mixed with the water supply. It was not very successful to calculate the amount of human waste from leaking sewage pipes. Dog and cat dung is also stored in and out of the city.

2. What are the five harmful microorganisms?

Species of Microorganisms are bacteria, archaea, fungi, protozoa, Algae, and bacteria. Examples of Microbiological Oils: Escherichia coli O157: H7, Mycobacterium tuberculosis, Streptococcus mutans, Salmonella enteric and Chlamydophila pneumonia.

3. Are all microorganisms harmful?

Invisible organisms — including germs, fungi, and bacteria — can make you sick. But you may not realise that billions of germs live inside your body right now. Most do not hurt at all. In fact, they help you digest food, protect you from disease, and maintain your reproductive health.

4. What is a carrier of disease?

Some germs do not directly infect their pathogens, instead, they carry a carrier - a living organism that carries the virus that causes the disease without showing any significant symptoms. An example of the mosquito repellent is Anopheles - which carries protozoan Plasmodium vivax.