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Bacteria. Our invisible friends. Bacteria are prokaryotes. Pro – before Karyon – nucleus The simplest forms of life are prokaryotes. Earth’s first cells were prokaryotes. Lots of Them!. Prokaryotes are Earth’s most abundant life forms. They can survive in many environments.
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Bacteria Our invisible friends
Bacteria are prokaryotes • Pro – before • Karyon – nucleus • The simplest forms of life are prokaryotes. • Earth’s first cells were prokaryotes.
Lots of Them! • Prokaryotes are Earth’s most abundant life forms. • They can survive in many environments. • They can get energy from many different sources.
Prokaryote Review • Mostly single-celled • No nucleus or organelles • Circular chromosomes • Cell walls • Reproduce mostly asexually • Anaerobic or aerobic • Heterotrophic or autotrophic
Archaebacteria • Methane producers – anaerobic • Halophiles • Halo = salt • Philia = love • Thermophiles • Thermo = heat
Eubacteria • Parasitic heterotrophs (Streptococcus) • Saprophages • Sapro = death • Phage = eat • Cyanobacteria (blue-green algae) • Photosynthetic • Chemosynthetic autotrophs (Rhizobium)
Bacteria are Named by Shape • Cocci (ball-shaped) • Streptococcus mutans • Bacillus (rod-shaped) • Clostridium botulinum • Spirilli (spiral-shaped) • Treponema palladium
Germ Theory of Disease • Joseph Lister – Aseptic Techniques • Robert Koch – Germ Theory • A specific microorganism causes a specific disease