chapter 7. 1. spherical – cocci (singular coccus) 2. rod shaped – bacilli (singular bacillus) ...
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BACTERIAChapter 7
3 BASIC SHAPES OF BACTERIA
1. spherical – cocci (singular coccus)
2. rod shaped – bacilli (singular bacillus)
3. spiral – spirilla (singular spirillum)
PARTS OF BACTERIAL CELL Cytoplasm Cell membrane cell wall 1 circular
chromosome Plasmid
(smaller piece of DNA)
ribosomes
SPECIAL FEATURES capsule – thick
sticky gel –like layer around outside of cell wall
Protects bacteria from destruction by other cells
Help it to stick to surfaces
Slime layer – helps bacteria to stick to surfaces Reduces water loss
Flagella – help them to move
CHARACTERISTICS OF BACTERIA Found
everywhere on earth
Smaller than plant and animal cells
One-celled organism
Grow alone or in groups or chains
REPRODUCTION Sexual
reproduction – conjugationRequires a joining
of cells to exchange genetic material
Draw this diagram
REPRODUCTION Asexual -
binary fissionSplitting in two
OBTAINING FOOD Producers Autotrophs Make own food –
contain chlorophyll
Consumers – eat other organisms
Heterotrophs Consumers –
Decompose dead or decaying matter
Parasites Live off living organisms
and absorb nutrition from hosts.
E. coli
AEROBIC AND ANAEROBIC Aerobic –
bacteria that need oxygen to live
Anaerobic – bacteria that do not need oxygen to live
ARCHAEBACTERIA Found in extreme
conditions Salty - halophites Boiling hot-
thermophites acidic Methane
producers Muddy swamps Intestines of cattleUs
Pneumonia bacteria
BACTERIA SUBGROUPS Eubacteria -
cyanobacteria – blue green bacteria Make own food O2 waste Red, black, or yellow
Importance; Make Oxygen for
organisms that live in water
Used as food source
CYANOBACTERIA Eubacteria Autotrophs Cyano – blue/green
bacteria - yellow, red
and black Single celled Colonies – chains or
filaments Reproduce – fission Used as food by fish
Disadvantages:Bloom – mat of
bubbly green slime on water
Resources used up and bacterial die
Consumer bacteria feed on it and use up oxygen. Organisms that live in water die
WHAT KINDS OF BACTERIA ARE SHOWN BELOW?
LAB PAGE 192 TEXTBOOK
Nostoc
Oscillatoria
GloeocapsaAnabaena
Page 191 Numbers;1,2,3,5,6On loose leaf to be handed in
BACTERIA IN YOUR LIFESECTION 8-2 Beneficial bacteria
Saprophyte – organism that uses dead material as food and energy
Digest dead organismsRecycle nutrientsUsed to make cheese, sauerkraut,
vinegar,medications
NITROGEN FIXING BACTERIA
Beneficial bacteria Nodules – found on
plants that contain nitrogen fixing bacteria - legumes Ex. Peanuts, peas, soybeans Take nitrogen from air for
plants to use In return plant gives bacteria
sugar. Helps fertilize soil Helps other organisms to
produce protein Mutualism – organisms help
each other to live
HARMFUL BACTERIA Pathogen – any organism that
produces disease Ex: anthrax in cattle Diphtheria, tetanus, whooping cough Antibiotic – substance produced by
one organism that inhibits or kills another organismEx. Penicillin, prevents bacteria from
making cell walls. W/o cannot survive
VACCINE- Made from damaged particles from
bacteria’s cell walls, or killed or weakened bacteria cells.
- When injected the white blood cells recognize that bacteria and attack it.
TOXINS Produced by
pathogens Poisons Ex. Botulism – food
poisoning - can
cause paralysis and
death Clostridium
botulumum
Endospores – thick walled structure around bacteria to protect them from heat or dryness
- can exist for years until right conditions for growth
- some anaerobic and grow in cans
HOW ENDOSPORES ARE FORMED
1. Copy of chromosome 2. Cell membrane pinches
off copy 3. Mother cell swallows
daughter cell. Now, two membranes layers surround daughter cell
4. Thick wall/spore coat is made
5. Tough outer coating made
6. Mother cell withers away.
7. Spore made.
PASTEURIZATION Process of heating food to a
temperature that kills harmful bacteria
COMPLETE IN NOTEBOOK Page 191
Self Check 1,2,3,4,5
Applying Math
Page 205 Applying Math 29 and 30
A. Draw and label this bacterial cell.
1
7
6
5
4
32
What shape bacteria?
B