Microorganisms, also called microbes, are tiny organisms that can only be seen with a microscope. They are classified into five major groups: bacteria, viruses, protozoa, fungi, and algae. Bacteria are single-celled organisms that live in diverse environments and have both helpful and harmful relationships with humans. Fungi are plant-like organisms that lack chlorophyll and are found in warm, moist places where they can be beneficial or detrimental to humans. Protozoa are unicellular microbes that can move and capture food themselves. Algae contain chlorophyll and can produce their own food through photosynthesis, helping to supply food for aquatic animals. Viruses can only reproduce inside host organisms and cause

1. MADE BY:
ABDEALI SAIFY
CLASS- 7TH

2. WHAT ARE MICRORGANISMS?
Microorganisms- is derived from a greek word micros (small) and
organismos(organism) also called as microbes.they can be
unicellular as well as multicellular.they are too small and can be
seen with the help of micoscope.the study of microrganisms is
called microbiology.Microorganisms are classified into five
major groups mainly :
1.Bacteria
2.Virus
3.Protozoa
4.Fungi
5.Algae

3. BACTERIA
Bacteria are microscopic, single-celledorganisms that thrive in diverse environments.
These organisms can live in soil, the ocean and insidethe human gut.Humans'
relationship withbacteria is complex. Sometimesbacteria lend us a helpinghand, such
as by curdling milkinto yogurt or helpingwith our digestion
Bacteria are like eukaryotic cells in thatthey have cytoplasm, ribosomes, and a plasma
membrane. bacterial cell lack in circular DNA in thenucleoid,
membrane-boundorganelles, cellwall,and flagella.

4. FUNGI
plant -like organisms that do not contain chlorophyll are called
Fungi.Fungi may be unicellular (Yeast) or multicellular (Bread
mould) and are found in warm and moist places.Fungi can be
heterotrophic, saprophytic or parasitic in nutrition.Examples:
Yeast, Rhizopus (Bread mould), mushrooms, puffballs.Humans
use fungi for many purposes, including as food or in the
preparation of food.Humans also use fungi for pest control.In
addition, fungi can be used to produce citric acid,
antibiotics, and human hormones.

5. PROTOZOA
Protozoa: these are unicellular microscopic organisms similar to
animals that can move about to capture food and are heterotrophic
in nature. Some of them are autotrophic (prepare their own food),
while others are heterotrophic (depend on others for their
food)they are mostly aquatic in nature. Amoeba, protozoa play an
important role in mineralizing nutrients, making them available
for use by plants and other soil organisms.Paramecium are some
examples of protozoa.

6. ALGAE
Algae are simple plant- like organisms which are usually aquatic in
nature.They contain a cell wall and chlorophyll and can make
their own food by photosynthesis.Algae can be unicellular or
multicellular.Some of the common examples are diatoms,
chlamydomonas, and seaweed.it helps in supplying food to
aquatic animals and also produces oxygen gas that can
be used for respiration.

7. VIRUS
Viruses are microscopic organisms that come alive only
when inside a host organism (that is they reproduce only
inside another organism) .The host organism could be a
bacterium, plant or animal. Common ailments like cold and
influenza (flu) are caused by viruses.The name is from a
latin word meaning “slimy liquid” or “poison.”