KINGDOM MONERA (BACTERIA)

What makes this kingdom unique?  Most abundant organisms on Earth  Outnumber all other organisms combined  More in a handful of dirt than the total number of people who have ever lived

Characteristics Prokaryotes: no nucleus or membrane-bound organelles

Characteristics  Smaller than smallest eukaryotes  All are unicellular  Now considered two kingdoms: Archaebacteria and Eubacteria prokaryotes eukaryotes smaller than

KINGDOM ARCHAEBACTERIA  Archae = ancient  Evolution considers them the first organisms  Can live where no others can

Types of Archaebacteria: methanogens  Convert CO 2 into methane gas  O 2 is poison to them  Require anaerobic conditions (i.e. sewage or swamp)  Thrive in cow and human intestines

Types of Archaebacteria: thermoacidophiles  Love hot and acidic environment  Many are chemosynthetic volcanic vents hydrothermal vents

Types of Archaebacteria: extreme halophiles  Salt-loving  Great Salt Lake and Dead Sea  Use salt to generate ATP

KINGDOM EUBACTERIA  Classified in two ways: shape and stain  3 different shapes  Unicellular or colonies

1. SPHERE-SHAPED: COCCUS Diplococcus - two Staphylococcus – clusters Streptococcus – strings

2. ROD-SHAPED: BACILLUS Diplobacillus - two Streptobacillus - strings

3. CORK SCREW: SPIRILLUM

REACTION TO STAIN  Gram stain used for classification  Differing reaction based on cell wall Cell membrane (Phospholipid) Peptidoglycan (Protein + sugar) Lipopolysaccharide (Fat + sugar) Gram-negativeGram-positive

GRAM-POSITIVE EUBACTERIA  Absorb Gram stain and appear purple  Simple cell wall antibiotics are effective

GRAM-NEGATIVE EUBACTERIA  Do not absorb Gram stain  Absorb a secondary pink stain  Complex cell wall antibiotics are ineffective

ALEXANDER FLEMING  Scottish bacteriologist  Grew Staphylococcus bacteria in dish  Contaminated by Penicillium mold  Mold inhibited the bacteria1 st antibiotic

ANTIBIOTICS  Fight pathogens  Interfere with formation of cell walls  Many obtained from bacteria or fungi  Others produced synthetically

NATURAL BODY DEFENSES 1.SKIN 2.MUCUS 3.TEARS 4.STOMACH ACID 5.LEUCOCYTES 6.ANTIBODIES

CELLULAR RESPIRATION 1. Obligate aerobes require oxygen (i.e. Mycobacterium tuberculosis) 2. Facultative anaerobes can use oxygen when available but do not require it (i.e. Escherichia coli) 3. Obligate anaerobes cannot grow in the presence of oxygen (i.e. Clostridium tetani)

BACTERIA IN NATURE ~ Photosynthesis  Cyanobacteria are photosynthetic O 2  Availability of O 2 advent of aerobic organisms Oscillatoria Nostoc Anabaena

BACTERIA IN NATURE ~ Nitrogen fixers  Rhizobacteria grow in roots of soybeans, alfalfa  Convert atmospheric N 2 into usable form for plants

BACTERIA IN NATURE ~ Decomposers  Break down matter into simpler substances  Nutrients released into the soil

BACTERIA IN NATURE ~ Living Together (Symbioisis)  Mutualism: both organisms benefit  Bacteria and Komodo dragons  Bacteria-laden saliva  Mouth provides habitat

BACTERIA IN NATURE ~ Eutrophication Excess phosphates and nitrates Cyanobacteria thrive Death and decomposition Decomposition requires oxygen Fish kill

BACTERIA and INDUSTRY ~ Food Production  Ferment lactose in milk sour cream, yogurt, and buttermilk  Digest protein in milk ricotta cheese and cottage cheese  Fermentation pickles and sauerkraut

BACTERIA and INDUSTRY ~ Genetic engineering  Insert genes into bacteria  Develop medical products (i.e. synthetic insulin)  Develop disease-resistant crops (i.e. Bt corn)

Bt Corn Bt is a naturally-occurring soilborne bacterium that is found worldwide. This bacterium produces crystal-like proteins that selectively kill specific groups of insects. Once the protein is eaten, insects stop feeding within two hours of a first bite and, if enough toxin is eaten, die within two or three days. Plant geneticists create Bt corn by inserting selected exotic DNA into the corn plant's own DNA. Bt corn improves European corn borer control.