BACTERIA KEY CONCEPTS
1. LIVING UNICELLULAR ORGANISMS 2. PROKARYOTIC = NO NUCLEUS CONSISTS OF 2 KINGDOMS: EUBACTERIA AND ARCHAEBACTERIA
3. Archaebacteria Eubacteria Smaller kingdom Live in extreme environments: Thermophiles Halophiles Methanogens May be ancestors of eukaryotes (DNA is similar) Lack peptidoglycan Eubacteria Larger kingdom (more members) Common Live everywhere Have peptidoglycan in cell walls
3 KINDS OF ARCHAEBACTERIA HALOPHILES (SALTY WATER) THERMOPHILES (HOT) METHANOGENS (COW INTESTINES, produce methane)
CLASSIFICATION OF BACTERIA What shape they are. What type of cell wall they have. Their movement characteristics. Their specific mode of nutrition. The way they get energy (ATP) from food.
3 SHAPES OF BACTERIA COCCI BACILLI SPIRILLA
4. Bacillus (Bacilli)
4. Coccus (Cocci)
4. Spirillum (Spirilla)
Prefixes 4. Diplo = 2 Strepto = chain Staphylo = clumps
Cell Wall Type: Gram staining Used to find out which type of cell wall a eubacterium has. Gram + has a thick peptidoglycan cell wall. (purple) 5. Gram – had a thinner cell wall with an outer lipid layer. (pink/red) Can be antibiotic resistant
Types of Movement 6. Flagella: tail used for movement Cilia: short hairlike projections Pili: used for cell-to-cell contact Some glide, wiggle, slide. Some do not move at all.
Types of Nutrition Autotrophic: makes own food 7. Chemoautotroph: uses chemicals Photoautotroph: uses sunlight Heterotrophic: consumes food (most) Chemoheterotroph-takes in organic molecules Photoheterotroph (are photosynthetic and take in compounds)
Releasing energy from food: 8. Obligate aerobe: require oxygen Obligate anaerobe: must live in the absence of oxygen (ex: Clostridium botulinum-in canned food) 9. Facultative anaerobe: can survive with or without oxygen (E. coli-lives anaerobically in lg. intestine, but aerobically in sewage or contaminated water)
REPRODUCTION (p. 475) 10. Binary fission: asexual, splits in two 11. Conjugation: sexual, exchange genetic info through a hollow bridge that forms between two bacterial cells 12. Spore formation: when conditions unfavorable, spore forms around DNA to protect it (endospore)
BENEFICIAL BACTERIA 13. MOST BACTERIA ARE HELPFUL (like in our intestines!) 14. DECOMPOSERS, recycle nutrients BIOREMEDIATION: DIGEST HARMFUL CHEMICALS, like oil NITROGEN FIXATION: IN LEGUMES (SUCH AS SOYBEANS) FOOD: YOGURT, CHEESE, PICKLES, SOUR CREAM, BUTTERMILK, ETC.
15. BACTERIA AND ILLNESSES ANTHRAX TETANUS Tooth decay Strep throat CHOLERA: SPREADS BY CONTAMINATED WATER Staph infection BUBONIC PLAGUE: DISEASE CARRIED BY RODENTS TO HUMANS
Food poisoning…… Salmonella E. coli Botulism
Pathogens Bacteria can cause disease in two ways: 16. Produce toxins Damage cells
Control—prevent bacterial growth 17. Sterilization: heat, disinfectants Food processing: boiling, canning, salting, refrigeration (doesn’t kill, just slows down) Antibiotic: medicine that kills bacteria
Antibiotic Resistance Many bacteria have evolved resistance to antibiotics, so we are constantly having to change antibiotics. Antibiotic resistance article link 18. Describe what it means…