What are useful and harmful microorganisms?
Microorganisms are small organisms invisible to the naked eye because of their extremely small size. They are grouped into various groups like Bacteria, fungi, algae, protozoa and viruses.
Many of these organisms are useful to human and nature while some are harmful and even cause diseases.
| Type | Useful microorganisms | Harmful microorganisms |
|---|---|---|
| Bacteria | Lactobacillus (curd bacteria) | Salmonella typhi (causes typhoid) |
| Fungi | Penicillium notatum (to make antibiotics) | Trichophyton rubrum (Athlete’s foot) |
| Algae | Anabaena (biological nitrogen fixation) | blue-green algae and red tides (produce toxins) |
| Protozoa | Paramecium (kills harmful bacteria) | Plasmodium (malaria fever) |
| Virus | polio, chicken pox (to make vaccines) | HIV (causes AIDS) |
Harmful effects of microorganisms:
Bacteria: Causes various diseases such as typhoid, diarrhea, and cholera.
Fungi: Causes a large number of diseases in plants and in animals such as rust diseases in plants, fruit rot in apple, red rot in sugar cane and ring worm disease in human beings.
Algae: Algal boom in water (rapid growth of algae) causes poisonous effect after they die, which in turn results in the death of aquatic organisms.
Protozoa: Causes Amoebic dysentery, pyorrhoea and sleeping sickness etc.
Virus: Cause small fox, common cold, influenza, herpes, hepatitis, polio and rabies.