BACTERIAWHERE: Everywhere--> *Food
*water
*soil
*your BODY!
AGE: ...probably the oldest life form on Earth
*fossil bacteria found in rocks
3.5 billion years old!
DESCRIPTION: single-celled organism
*prokaryotic
WITHOUT A NUCLEUS
BACTERIA Names...…given by the COLONY PREFIX and the SHAPE SUFFIX
Examples
STREPTOCOCCUS
chains of round bacteria
STREPTO= chains COCCUS= round+
BACTERIA THAT CAUSE
DISEASE
• Some bacteria cause
diseases. Disease causing
bacteria are called
pathogenic.
Staphylo -
bacteria occur
in clumps, such
as this
staphylococcus
bacteria that
causes common
infections of
cuts
Strepto-
bacteria occur
in chains of
bacteria, such
as this
streptococcus
bacteria that
causes some
types of sore
throats
Leprosy is a
bacterial
infection
that
decreases
blood flow to
the
extremities
resulting in
the
deterioration
of toes, ears,
the nose and
the fingers.
• Gram-positive bacteria tend to be
killed by penicillin and detergents.
• Gram-negative bacteria are more
resistant to antibiotics.
Gram Stain
BACTERIA Survival...--> Most bacteria obtain food from other living things.
(like us)
--> some eat dead things -DECOMPOSERS
--> some are PARASITES -. live off other living things
*these may cause DISEASE
*or may actually HELP the host!
--> Example of “helping” Bacteria:
Bacteria in your intestine helps with
digestion and produces vitamin K.
Harmful BACTERIAFOOD SPOILAGE
Botulism caused by
Clostridium botulinum
E. coli
found in beef-->
Salmonella
Controlling the growth of BACTERIAHow to limit BACTERIA REPRODUCTION
** TEMPERATURE (Pasteurization)
(Pasteurization)
Louis Pasteur
**CHEMICALS
heat kills bacteria
*boil *steam
*Bleach *iodine
Controlling the growth of BACTERIA (more!)
** Removing MOISTURE
*No water,
no bacteria!
SALTING**RADIATION
*use of radiation to “zap” bacteria!
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STRUCTURE OF BACTERIAStructure Function
Cell Wall Protects and gives shape
Gelatinlike
capsule
Protects against antibodies Helps the bacteria stick to things.
Cell Membrane
Regulates movement of materials
Cytoplasm Contains DNA, ribosomes, essential compounds
Chromo-some
Carries genetic information
Ribosome Makes proteins
Flagellum Moves the cell
CLASSIFICATION OF
BACTERIA
• Bacteria are classified into two kingdoms.
• Eubacteria
• Archaebacteria