Microorganisms – Friends and Foe
- Microorganisms are too small and are not visible to the unaided eye.
- Microorganisms are found in air, water and in the bodies of plants and animals.
- Diseases like dysentery and malaria are caused by protozoans whereas typhoid and tuberculosis (TB) are bacterial diseases.
- Microorganisms may be unicellular or multicellular.
- Microorganisms have been used for the production of alcohol since ages they are also used in cleaning up of the environment.
- Microorganisms can live in all kinds of environment, ranging from ice cold climate to hot springs and deserts to marshy lands.
- Microorganisms like amoeba can live alone, while fungi and bacteria may live in colonies.
- Viruses are also microscopic they reproduce only inside the cells of the host organism, which may be a bacterium, plant or animal.
- Viruses are quite different from other microorganisms. They reproduce only inside the host organism; bacterium, plant or animal cell.
- Curd contains several microorganisms. Of these, the bacterium Lactobacillus promotes the formation of curd. It multiplies in milk and converts it into curd.
- Microorganisms play an important role in our lives. Some of them are beneficial in many ways whereas some others are harmful and cause diseases.
- These days a number of antibiotics are being produced from bacteria and fungi Streptomycin, tetracycline and erythromycin are some of the commonly known antibiotics.
- Microorganisms are used for the large scale production of alcohol, wine and acetic acid (vinegar)
- Antibiotics are even mixed with the feed of livestock and poultry to check microbial infection in animals. They are also used to control many plant diseases.
- These days’ vaccines are made on a large scale from microorganisms to protect humans and other animals from several diseases.
- Some bacteria are able to fix nitrogen from the atmosphere to enrich soil with nitrogen and increase its fertility. These microbes are commonly called biological nitrogen fixers.
- The microorganisms decompose dead organic waste of plants and animals converting them into simple substances.
- Microorganisms can be used to degrade the harmful and smelly substances and thereby clean up the environment.
- The plant waste is always converted into manure by the action of microbes.
- The disease causing micro organisms are called as Pathogens
- Pathogens enter our body through the air we breathe, the water we drink or the food we eat.
- Pathogens can also get transmitted by direct contact with an infected person or carried through an animal.
- Robert Köch (1876) discovered the bacterium (Bacillus anthracis) which causes anthrax disease.
- Anthrax is a dangerous human and cattle disease caused by a bacterium.
- Several microorganisms cause diseases in plants like wheat, rice, potato, sugarcane, orange, apple and others. the diseases reduce the yield of crops.
- Food poisoning could be due to the consumption of food spoilt by some microorganisms.
- Microorganisms that grow on our food sometimes produce toxic These make the food poisonous causing serious illness and even death.
- Sodium benzoate and sodium metabisulphite are common preservatives.
- Preservatives are also used in the jams and squashes to check their spoilage.
- Common salt has been used to preserve meat and fish for ages.
- Meat and fish are covered with dry salt to check the growth of
- Sugar reduces the moisture content which inhibits the growth of bacteria which spoil food.
- Use of oil and vinegar prevents spoilage of pickles because bacteria cannot live in such an environment.
- These days’ dry fruits and even vegetables are sold in sealed air tight packets to prevent the attack of
- Our atmosphere has 78% nitrogen gas.
- Some microorganisms reside in the root nodules of leguminous They can fix nitrogen from air into soil and increase the soil fertility.
- Nitrogen is one of the essential constituents of all living organisms as part of proteins, chlorophyll, nucleic acids and vitamins.
- Sometimes nitrogen gets fixed through the action of lightning.
- Certain bacteria and blue green algae present in the soil fix nitrogen from the atmosphere and convert into compounds of nitrogen.
- When plants and animals die, bacteria and fungi present in the soil convert the nitrogenous wastes into nitrogenous compounds to be used by plants again.
- Certain bacteria convert compounds of nitrogen present in the soil into nitrogen gas which is released to the atmosphere.
- When nitrogen is converted into these usable compounds, it can be utilized by plants from the soil through their root system.
- Nitrogen is then used for the synthesis of plant proteins and other compounds.
0 Comments