PART I Chapter 18 Archaebacteria & Eubacteria
Phylogeny
Characteristics First living evidence on earth Unicellular Prokaryotes (No membrane-bound organelles) Cell wall with internal plasma membrane Found everywhere
Bacteria
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
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
Flagella
Capsules
Endospores
Classification: Three Basic Shapes Cocci - Spheres Bacilli - Rods Spirilli - Spiral
Classification: Gram stain – Cell wall type Thick – Purple Stain = “Gram Positive” Thin - Pink Stain = “Gram Negative”
Growth Patterns Diplo- pairs Staphylo- clusters Strepto- chains
Streptococci
Pneumonia
PART II Chapter 18 Archaebacteria & Eubacteria
Archaebacteria – ancient bacteria Methanogens Live in: Oxygen-free environment Produce methane gas Halophiles Live in: Salt water Acidophiles: Live in: Hot, acidic water
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
Cyanobacteria - “blue-green bacteria” Algae + Bacteria
Sulfur Bacteria
Beneficial Bacteria Nitrogen fixation –Converts nitrogen into ammonia –a form that plants can use Nodules –A symbiotic relationship between bacteria and plants
(Beneficial Bacteria) Saprophytes (decomposers) –Breaks down dead organisms and decaying matter –Returns nutrients to soil
(Beneficial Bacteria) Make food: –Cheese –Pickles –Yogurt –Vinegar –Sauerkraut
Cellular Respiration Obligate Aerobes Obligate Anaerobes Need OxygenDie from Oxygen
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)
Antibiotics: ~ Destroys cell wall of bacteria ~ Creates holes in the cell walls Sir Alexander Fleming discovered Penicillium notatum
Air-Born
Air-Born Bacteria
Reproduction Asexual Binary Fission –Cell division Rapid - 20 min. Sexual Conjugation – exchange genetic material Pili/pilus - bridge
Binary Fission: Asexual Reproduction
Conjugation - Sexual Reproduction