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PART I Chapter 18 Archaebacteria & Eubacteria
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Phylogeny
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Characteristics First living evidence on earth Unicellular Prokaryotes (No membrane-bound organelles) Cell wall with internal plasma membrane Found everywhere
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Bacteria
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Bacteria Structures Cell wall – provides support and protection to the cell Plasma membrane – flexible, selectively permeable boundary that controls what enters and leaves the cell Cytoplasm – semi-fluid material inside the cell’s plasma membrane Ribosome – organelle that helps to manufacture proteins DNA - stores and communicates genetic information for the cell
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Bacteria Structures Pilus/pili - hairlike protrusion –to stick to surfaces –a bridge for sexual reproduction Flagellum - long, whiplike protrusion, for moving Capsule - sticky layers around cell wall Toxin - a powerful poison Endospore – found in some bacteria - resists harsh environments
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Flagella
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Capsules
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Endospores
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Classification: Three Basic Shapes Cocci - Spheres Bacilli - Rods Spirilli - Spiral
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Classification: Gram stain – Cell wall type Thick – Purple Stain = “Gram Positive” Thin - Pink Stain = “Gram Negative”
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Growth Patterns Diplo- pairs Staphylo- clusters Strepto- chains
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Streptococci
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Pneumonia
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PART II Chapter 18 Archaebacteria & Eubacteria
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Archaebacteria – ancient bacteria Methanogens Live in: Oxygen-free environment Produce methane gas Halophiles Live in: Salt water Acidophiles: Live in: Hot, acidic water
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Eubacteria - “True” bacteria Heterotrophs Photosynthetic Autotrophs Chemosynthetic Autotrophs Saprophytes (decomposers) Need sunlight to make food Need sulfur & nitrogen to make food Parasites (cause disease) Example: Cyanobacteria Nitrogen fixation (FIX the nitrogen) Live in more habitable environments
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Cyanobacteria - “blue-green bacteria” Algae + Bacteria
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Sulfur Bacteria
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Beneficial Bacteria Nitrogen fixation –Converts nitrogen into ammonia –a form that plants can use Nodules –A symbiotic relationship between bacteria and plants
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(Beneficial Bacteria) Saprophytes (decomposers) –Breaks down dead organisms and decaying matter –Returns nutrients to soil
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(Beneficial Bacteria) Make food: –Cheese –Pickles –Yogurt –Vinegar –Sauerkraut
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Cellular Respiration Obligate Aerobes Obligate Anaerobes Need OxygenDie from Oxygen
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Pathogenic Bacteria – disease-causing bacteria Pathogen – an organism that causes disease Produce toxins Damage host’s tissues Enter through openings in body (via air, food, water)
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Antibiotics: ~ Destroys cell wall of bacteria ~ Creates holes in the cell walls Sir Alexander Fleming 1928 - discovered Penicillium notatum
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Air-Born
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Air-Born Bacteria
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Reproduction Asexual Binary Fission –Cell division Rapid - 20 min. Sexual Conjugation – exchange genetic material Pili/pilus - bridge
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Binary Fission: Asexual Reproduction
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Conjugation - Sexual Reproduction
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