Download BACTERIA PROKARYOTES Traditionally all prokaryotes were

9/28/2011
BACTERIA
PROKARYOTES
Traditionally all
prokaryotes were classified
as Monerans
Also known as bacteria
(pl.) or bacterium (s.)
Presently, the prokaryotes
are divided into two
kingdoms.
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1. ARCHAEBACTERIA
Comes
from the Greek word archaio
which means “ancient”.
All live in harsh environments.
2. EUBACTERIA
Larger
of the two kingdoms.
Live almost everywhere.
Vital for life functions and industry
Both helpful and harmful
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FACTS ABOUT BACTERIA:
Found everywhere
Very small. Much smaller than any cell in our
body.(1-5 um)
No membrane-bound structures or nucleus.
(prokaryotes)
Usually surrounded by a cell wall and a capsule
for additional protection.
GENERAL STRUCTURE:
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GENERAL STRUCTURE
CLASSIFICATION ACCORDING TO SHAPE.
1.
Coccus (s.) or
Cocci
(pl.)(spherical)
Can be single cells
Pairs
Chains
Clusters
Examples:
Streptococcus
Staphylococcus
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CLASSIFICATION ACCORDING TO SHAPE.
2. Bacillus(s.)
Bacilli
(pl.) (rod)
Single cells
Pairs
Chains
Example
Anthrax
(Bacillus
anthracis)
Escherichia
coli
CLASSIFICATION ACCORDING TO SHAPE.
3.
Spirochetes (spiral)
Only
cells
exist as single
Examples:
Syphilis
(Treponema
pallidum)
Lyme Disease
(Borrelia
burgdorferi)
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REPRODUCTION
All
reproduce asexually
Usually through binary fission
Under certain conditions, bacteria can
reproduce very quickly
A small colony can double in 20
minutes.
BINARY FISSION
The most common type
of asexual reproduction.
A single cell splits to
form two daughter
cells.
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EXCHANGE OF DNA
Conjugation is the
transferred of
genes between
two bacterial
cells that are
temporarily
joined.
ENDOSPORES
A
thick covering
around the DNA that
allows the bacterium
to remain dormant
for long periods of
time. If necessary,
many years.
Examples: Anthrax
(Bacillus anthracis)
Tetanus(Clostridium
tetani)
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HELPFUL BACTERIA
Decompose food
wastes
Produce vitamins
Produce antibodies
Genetic engineering
Decomposition of
dead plants and
animals
Industry &
agriculture
Nitrogen-fixing
bacteria
NITROGEN FIXING BACTERIA
Found on the roots of
plants.
Can be helpful in
‘fixing’ nitrogen for
plant use.
Rhizobium nodules on
roots of soybeans
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COMMON BACTERIAL DISEASES:
Lyme
disease
Tetanus
Strep throat
Tuberculosis
Toxigenic E. coli
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