microorganism : friend and foe

MICROORGANISMS AND MICROBES ABOUT MICROORGANISMS TYPES OF MICROORGANISMS VIRUSES

DISEASES

INDEX

MICROORGANISMS AND MICROBESHowever, there `are other living organisms around us

which we are normally cannot see . These are

called microorganisms or microbes . For example, during the rainy season

moist bread gets spoilt and its surface gets covered

with greyish white patches .

IT IS AN

MICROORGANISMS

ABOUT MICROORGANISMSWater and soil are full of tiny organisms, thought

not all of them fall into the category of microbes.

Microorganisms or microbes are so small in size that they cannot be

seen with the unaided eye. That is why these are

called microorganisms or microbes .

Microorganisms are classified into four major groups. These groups are bacteria, fungi, protozoa and

some algae. Some of these common Microorganisms are

shown in figs. 2.1-2.4.

TYPES OF MICROORGANISMS

Bacteria are a large domain of single-celled, prokaryote

microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from

spheres to rods and spirals. There are typically 40 million bacterial cells

in a gram of soil and a million bacterial cells in a milli litre of fresh water. Bacteria are vital in recycling

nutrients.

BACTERIA

TWO TYPES OF

BACTERIA

ROD-SHAPED SPIRAL BACTERIA

 A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds (British English: moulds), as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria.

.

FUNGUS

BREAD MOULD ASPERGILLUS

Protozoa are a diverse group of single cell eukaryotic organisms, many of which

are motile. Historically protozoa were defined as single cell protests with

animal-like behavior, e.g. movement. Protozoa were regarded as the partner group of protests to protophyta which

have plant-like behavior, e.g. photosynthesis

PROTOZOA

EXAMPLE OF PROTOZOA

PARAMECIUM AMOEBA

Algae are a large and diverse group of simple, typically autotrophic

organisms, ranging from unicellular to multicellular forms, such as the

giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many distinct organs found in land

plants.

ALGAE

EXAMPLES OF ALGAE

CHLAMYDOMONAS SPIROGYRA

Viruses are also microscopic. They, however., reproduce only inside the

cells of the host organism. Which may be a bacterium, plant or animal. Some of the Viruses are shown in

fig.2.5. common ailments like cold, influenza (flu) and most coughs are caused by Viruses. Serious diseases like polio and chicken pox are also

caused by viruses.

VIRUSES

A virus is a small infectious agent that can replicate only inside the

living cells of organisms. Most viruses are too small to be seen directly with a light microscope.

Viruses infect all types of organisms, from animals and

plants to bacteria and archaea.

A VIRUS

EXAMPLES OF

VIRUSES

Diseases like dysentery and malaria are caused by protozoa (protozoan)

whereas typhoid and tuberculosis (TB) are bacterial diseases.

DISEASES

ANSWER THE

FOLLOWING QUESTION

What is microorganisms?

Name four types of microorganisms?

Give two examples of protozoa and fungi?

By which microorganisms dysentery and malaria is caused?

Name the serious diseases caused by viruses?

Where viruses reproduce ?

by which object we can see the microorganisms?

THE END

TAUGHT BYMR. PANKAJ KUKEREJASIR

PRESENTED BY

GROUP “A”TUSHAR SOLANKI , GAYATRI VALLAPH PAL , ARNAV SIKKEWAL , HIMANSHU GUPTA ,

ARYAN WAGADRE ,