GHANI KHAN CHOUDHURY INSTITUTE OF ENGINEERING AND TECHNOLOGY
A Centrally Funded Technical Institute (CFTI) under Ministry of Education Govt of India
Topic: Microorganisms
SUBJECT NAME: Biology PRESENTED BY
SUBJECT CODE: BSC-401 RIYA DEBNATH
REGISTRATION NUMBER: 243550120260
ROLL NO: 35530824075
INTRODUCTION
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Defination:
Microorganisms are microscopic living things that exist all
around us.
They include bacteria, viruses, fungi, protozoa, and algae.
Some are beneficial, while others cause diseases
Classification of Microorganisms
Bacteria: Single-celled prokaryotes, found everywhere.
Viruses: Non-living particles that require a host to replicate
.
Fungi: Includes yeasts, molds, and mushrooms.
Protozoa: Animal-like unicellular organisms.
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Algae: Photosynthetic, oxygen-producing organisms.
BACTERIA – A TINY BUT MIGHTY ORGANISM
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Defination:
Bacteria are microscopic, single-celled organisms that exist
in almost every environment.
Importance:
Some bacteria help with digestion
(Lactobacillus in yogurt).
Others assist in nitrogen fixation (Rhizobium in
soil).
Harmful bacteria can cause diseases like
tuberculosis and food poisoning.
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VIRUSES – THE MYSTERIOUS INVADERS
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Defination:
Viruses are extremely small infectious agents that can only
multiply inside a living host cell.
How They Spread:
Airborne Transmission:
Viruses like Influenza and COVID-19 spread through tiny
droplets in the air.
Direct Contact:
Diseases such as HIV/AIDS and rabies spread through physical
contact or body fluids.
Contaminated Surfaces:
Norovirus and other viruses can linger on surfaces and infect
individuals upon contact.
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PROTOZOA – THE UNSEEN PREDATORS
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Defination:
Protozoa are single-celled, animal-like microorganisms that move
using cilia, flagella, or pseudopodia.
Where They Are Found:
In freshwater, soil, and inside other organisms.
Examples:
Amoeba, Plasmodium
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ALGAE – THE MICROSCOPIC OXYGEN FACTORIES
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Defination:
Algae are simple, plant-like microorganisms that perform
photosynthesis and produce oxygen
Importance:
Algae form the base of the aquatic food chain.
Some species, such as spirulina, are used in food
supplements.
Certain algae contribute to biofuel production and
wastewater treatment.
Types of Algae:
Green Algae: Found in freshwater and marine environments.
Red Algae: Used in food products like sushi wraps.
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ROLE OF MICROORGANISMS IN DAILY LIFE
In Food:
Used in making bread, cheese, yogurt.
In Medicine:
Produce antibiotics and vaccines.
In Environment:
Help in decomposition and nutrient recycling.
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CONCLUSION
Microorganisms are essential to life on Earth.
They have both beneficial and harmful effects.
Their study helps in medicine, agriculture, and
industry.
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REFERENCES
Prescott, L. M., Harley, J. P., & Klein, D. A. (2002). Microbiology. McGraw-
Hill.
Madigan, M. T., Martinko, J. M., & Parker, J. (2003). Brock Biology of
Microorganisms. Prentice Hall.
Tortora, G. J., Funke, B. R., & Case, C. L. (2018). Microbiology: An
Introduction. Pearson.
World Health Organization (WHO) - www.who.int
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THANK
YOU
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