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Since bacteria are made of only other cells, the single cell of a
one cell, they are very cell. The bacterium can complete all of life
only way to see bacteria is to look functions by itself.
at them in a microscope. When
you look at bacteria in a Cell Wall
microscope, they usually have one
of three shapes. Think about your skin for a
moment. Although we may take it
Bacilli are shaped like rods, cocci for granted, our skin is extremely
are shaped like spheres, and important. This organ (yes, skin is
spirilli are shaped like spirals. an organ!) protects the body,
Using shapes to describe bacteria keeping most of the things that
helps scientists but bacteria into could hurt us from getting into our
groups, which is often called bodies.
classification.
Imagine for a minute if we didn’t
have skin. Dangerous things could
easily enter our body and make it
to our internal organs. Of course,
bacteria don’t have skin, because
they are only one cell, but they do
have something that acts like skin,
keeping things out if they could
harm the cell. This structure is
called a cell wall.
Figure 3 – Bacteria can be classified based
on their shape.
Structure of Bacteria
All bacteria have certain structures
inside of them. These structures
allow the bacterium (that’s the
singular form of bacteria) to go Figure 4 – The cell wall protects harmful
through its life cycle, complete the materials from entering the cell.
jobs it has to do, reproduce, and All bacteria have a cell wall. The
eventually die. Unlike a single cell cell wall is made of a mixture of
inside a multi-cellular organism like sugars and amino acids called
a plant or animal, which relies on peptidoglycan.
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