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

Special Features 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: Shape –Cocci (Spheres), Bacilli (Rods), Spirilli (Spiral) Gram stain - Cell wall type –Thick = Purple Stain = “Gram Positive” –Thin = Pink Stain = “Gram Negative” Growth patterns –Diplo- pairs –Staphylo- clusters –Strepto- chains

Shapes

Gram Stain

Growth Patterns

Streptococci

Pneumonia

PART II Chapter 18 Archaebacteria & Eubacteria

Archaebacteria – ancient bacteria Methanogens Live in: Oxygen-free env. Produce methane gas Halophiles Live in: Salt water Acidophiles: Live in: Hot, acidic water

Eubacteria - “True” bacteria Live in more habitable environments 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)

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