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Chapter 18.1 – Bacteria
I.
Kingdoms of Bacteria
A.
Archaea (Archaebacteria) – extremists that
survive where there is no oxygen
1.
Methane-producing Bacteria live in:
 swamps, bogs, volcano vents,
digestive tracts of mammals
 sewage plants – breakdown sewage
2.
Halophilic bacteria live in high salt
environments – Utah’s Great Salt
Lake, the Dead Sea
3.
Thermoacidophilic bacteria live in:
 Hot acidic sulfur springs
 thermal vents in the ocean floor
 volcanoes
B.
(Eu)Bacteria – live almost anywhere
oxygen is available
1.
Heterotrophs – get food from others,
mainly by decomposition
2.
Autotrophs – make own food:
 Photosynthetic – use sun
 Chemosynthetic – use chemicals
* Endospores survive conditions w/o food
II.
What is a Bacterium?
A.
Bacterial Parts:
1. Pili help bacteria stick to surfaces
2. Ribosomes make proteins
3. Chromosome & Plasmid contain
DNA
4. Capsule protects bacteria
5. Cell wall prevents bursting
6. Cell membrane regulates
substances
7. Flagella create movement
B.
Bacterial Shapes (draw)
1.
Round:
coccus / cocci
2.
Rod:
bacillus / bacilli
3.
Spiral:
spirillium / spirilli
OR spirochaetes
C.
Cell Walls – ID by Gram stain
1.
Gram +: much peptidoglycan,
turn bacteria purple
 treated with antibiotic penecillin
2.
Gram –: little peptidoglycan,
turn pink
 treated with antibiotic tetracycline
III.
Importance of Bacteria
A.
Nitrogen Fixation – bacteria that live
symbiotically with plants take N2 in the air
and change it into NH3 that plants can use
B.
Nutrient Recyclers – photosynthetic
bacteria replenish O2 in the atmosphere
C.
Producers of Food & Medicine
1.
Bacteria help create cheese, pickles,
yogurt, vinegar, sauerkraut,
sourdough bread, & chocolate!
2.
3.
In your intestines – E. coli bacteria
make vitamins (K clots blood)
Bacteria are used to make antibiotics
that kill other bacteria
IV.
Bacterial Diseases – harm in 2 ways:
A.
Interfere with function of a body tissue
1.
anthrax - Bacillus anthracis
2.
strep throat
3.
tuberculosis
B.
Release toxin that directly attacks the host
1.
dental cavities
2.
Lyme disease
3.
E. coli – Escherichia coli
4.
Botulism – Clostridium botulinum
5.
Tetanus
6.
Bubonic plague
7.
STDs: chlamydia, gonorrhea, syphilis