Prokaryotic single cellsShapes◦Sphere (cocci), Rod (bacilli), or Spiral (spirilli)

Organization◦Often clusters (staphylo-) or chains (strepto-)

Eubacteria have cell walls◦Gram negative have 2nd cell wall

◦Gram positive do not◦Negative = no antibiotics

Movement◦Many have flagella

Binary Fission – happens QUICKLY!

Obligate anaerobes◦Clostridium botulinum

Facultative anaerobes/aerobes◦E. coli

Obligate aerobes◦Tuberculosis

Autotrophic◦Photosynthetic (Cyanobacteria)◦Chemosynthetic (Methanogens)

Heterotrophic◦Parasitic (Tuberculosis)◦Decomposers

Beneficial◦Decomposers◦Manufacture of food – yogurt, cheese, pickles

Pathogens – disease-causing◦Food poisoning

Francesco Redi – Spontaneous Generation - 1665

AirborneWaterDirect contactVectors - transmitters of disease that carry the pathogens from one host to another

Antibiotics ◦1928 Fleming – penicillin mold toxic to bacteria

Antibiotic Resistance◦Not all bacteria die from antibiotics

◦People don’t finish prescription◦Over-prescribed

NONLIVING pathogens◦Do not metabolize, grow, or maintain homeostasis

Structure – RNA or DNA with protein capsid

Rely on living cells (hosts) for replication

Insertion of either the entire virus or just the DNA into the host cell

Some viruses turn the cell into a virus making factory, bursting the cell with new viruses

Other viruses replicate slowly and can lay dormant before take-over

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Vaccines – inject dead or weak virus so the body can form antibodies◦Edward Jenner – 1800s - smallpox

Anti-viral drugs – try to disable replication in some way