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Ch.18 Bacteria. Archaebacteria and Eubacteria. Archaebacteria- kingdom of first bacteria Are prokaryotic Have no membrane bound nucleus Have no organelles Three types: 1. live in oxygen free environment Produce methane gas Live in marshes, lakes and digestive tract of animals
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Archaebacteria and Eubacteria • Archaebacteria- kingdom of first bacteria • Are prokaryotic • Have no membrane bound nucleus • Have no organelles • Three types: • 1. live in oxygen free environment • Produce methane gas • Live in marshes, lakes and digestive tract of animals • Play big role in sewage breakdown in sewage plants
Archaebacteria continued • 2. live in water with high concentration of salt • Like in Utah’s Great Salt Lake and the Middle East’s dead sea • 3. live in acidic waters of sulfur springs. • Thrive near cracks deep in the Pacific Ocean floor • Are the producers for a unique underwater community
Eubacteria • 2nd kingdom of prokaryotes • Includes bacteria that live in a more hospitable environment • Eubacteria live almost everywhere • Some are heterotrophs – eat things for nutrients • Others are autotrophs- make their own food by photosynthesis • Cyanobacteria • Contain chlorophyll to trap sunlight • Live in ponds and are in long chains • Eg. Anabaena
A third type of eubacteria • Yet another type are those that are chemosynthetic • Use chemicals as energy source to make food instead of sunlight. • Import to farmers! Can turn atmospheric nitrogen into nitrogen usable to plants • Found on the roots of legumes (soy beans)
Identifying bacteria • Gram staining • Procedure that classifies bacteria as either gram + or gram – • Gram + bacteria stain purple • Gram – bacteria stain pink • Each type responds differently to different antibiotics • Substance that kills bacteria (anti- against… biotic- life) • Doctors must know what type of bacteria you are infected with to prescribe an effective antibiotic
Identifying bacteria • Shape is also used to identify bacteria • Three basic shapes: • Round (cocci) • Rod shaped (bacillus) • Spiral (spirillum) • Some have prefixes to describe their shape • Diplo- refers to paired arrangement • Staphylo- refers to an arrangement that resembles grapes • Strepto- refers to an arrangement of chains of cells