Recommandé
Contenu connexe
Tendances
Tendances (20)
En vedette
En vedette (20)
Similaire à Bacteria Structure and Functions
Similaire à Bacteria Structure and Functions (20)
Plus de ewaszolek
Plus de ewaszolek (20)
Bacteria Structure and Functions
- 3. Classification of Life 3 3
- 4. Three Domains of Life • Archaea – prokaryotes living in extreme habitats • Bacteria- Cyanobacteria and eubacteria • Eukarya – Protozoans, fungi, plants, & animals 4
- 5. Kingdoms of Bacteria Archaebacteria: Found in harsh environments Undersea volcanic vents, acidic hot springs, salty water 5
- 6. Archaebacteria 6
- 7. Kingdoms of Bacteria Eubacteria: Called the true bacteria Most bacteria are in this group Include photosynthetic Cyanobacteria 7
- 8. Eubacteria 8
- 9. Characteristics of Bacteria 9 9
- 10. Bacterial Structure • Microscopic prokaryotes • No nucleus or membrane- bound organelles • Contain ribosomes • Single, circular chromosome in nucleoid region 10
- 11. Bacterial Cell 11
- 12. Protection • Cell Wall made of Peptidoglycan • May have a sticky coating called the Capsule for attachment to host or other bacteria 12
- 13. Sticky Bacterial Capsule 13
- 14. Bacterial Structure PLASMIDS • Have small rings of DNA called Plasmids • Unicellular • Small in size (0.5 to 2μm ) [micometer] 14
- 15. 15
- 16. Bacterial Structure • Infoldings of cell membrane carry on photosynthesis & cellular respiration • Infoldings called Mesosomes 16
- 17. Mesosomes MESOSOME 17
- 18. Bacterial Structure • Most grow best at pH of 6.5 to 7.0 • Many act as decomposers recycling nutrients • Some cause disease 18
- 19. Staphylococcus Bacterial 19
- 20. Beneficial Uses of Bacteria 20
- 21. Useful Bacteria • Some bacteria can degrade oil • Used to clean up oil spills 21
- 22. Environmental Clean-up • Some bacteria eat oil and turn it into environmentally friendly chemicals. These bacteria are dumped into waters contaminated by oil spills. 22
- 23. Environmental Recycling • Bacteria are decomposers: they break down dead organisms into smaller chemicals which then go back into the soil. 23
- 24. Digestion • Many bacteria, such as human E. coli, live a warm and cozy life in your intestines. They help digest your food and make vitamins, such as Vitamin K (which is necessary for blood clotting). 24
- 25. Digestive Health • Beneficial bacteria, such as Lactobacillus, keep the “bad” bacteria in check, by competing with them for nutrients. 25
- 26. Medicines • The pharmaceutical industry uses some forms of bacteria to make vitamins and antibiotics. • Other bacteria can be used to produce insulin, which can be collected and given to people with diabetes. 26
- 27. Useful Bacteria • Other uses for bacteria include making yogurt, cheese, and buttermilk. 27
- 28. Fuel Production • Archaebacteria produce methane gas, which makes up 20% of the world’s natural gas used for fuel. 28
- 29. Flagella • Bacteria that are motile have appendages called flagella • Attached by Basal Body • A bacteria can have one or many flagella 29
- 30. Monotrichous Lophotrichous Amphitrichous Peritrichous 30
- 31. Question: What is this type of bacteria ? 31
- 32. Pili • Short protein appendages • Smaller than flagella • Adhere bacteria to surfaces • Used in conjugation for Exchange of genetic information • Aid Flotation by increasing buoyancy 32
- 33. Pili in Conjugation 33
- 34. Bacterial Shapes 34 34
- 35. Shapes Are Used to Classify • Bacillus: Rod shaped • Coccus: Spherical (round) • Vibrio: Comma shaped with flagella • Spirillum: Spiral shape • Spirochete: wormlike spiral shape 35
- 36. 36
- 37. Grouping of Bacteria • Diplo- Groups of two • Strepto- chains • Staphylo- Grapelike clusters 37
- 38. 38
- 39. 39
- 40. Diplococcus 40
- 41. Streptococcus Causes Strep Throat 41
- 42. Staphylococcus 42
- 43. Bacillus - E. coli 43
- 44. Bacterial Kingdoms 44 44
- 45. Archaebacteria • Lack peptidoglycan in cell walls • Have different lipids in their cell membrane • Different types of ribosomes • Very different gene sequences 45
- 46. Archaebacteria • Archaebacteria can live in extremely harsh environments • They do not require oxygen and can live in extremely salty environments as well as extremely hot environments • Called the Ancient bacteria 46
- 47. Archaebacteria • Subdivided into 3 groups: Methanogens Thermoacidophiles Extreme Halophiles 47
- 48. Methanogens • Live in anaerobic environments (no oxygen) • Get energy by changing H2 & CO2 into methane gas • Found in swamps, sewage treatment plants, digestive tracts of animals 48
- 49. Methanogens • Break down cellulose in a cow’s stomach • Produce marsh (methane) gas 49
- 50. Extreme Halophiles • Live in very salty water • Use salt to generate ATP (energy) • Dead Sea, Great Salt Lake inhabitants 50
- 51. Thermoacidophiles or Thermophiles • Live in extremely hot environments • Found in volcanic vents, hot springs, cracks on ocean floor that leak acid 51
- 52. Kingdom Eubacteria True Bacteria 52 52
- 53. Characteristics • 3 basic shapes (coccus, bacillus, spirilla) • Most are heterotrophic (can’t make their own food) • May be aerobic or anaerobic • Identified by Gram staining 53
- 54. Gram Staining • Developed in 1884 by Hans Gram • Bacteria treated with purple Crystal Violet & red Safranin stains • Cell walls either stain purple or reddish pink 54
- 55. Gram Positive • Have thick layer of peptidoglycan (protein-sugar complex) • Single lipid layer • Stain purple • Can be treated with antibiotics 55
- 56. Gram Positive Bacteria Lactobacilli (makes yogurt & buttermilk) Actinomycetes (make antibiotics) Clostridium (lockjaw bacteria) Streptococcus (strep throat) Staphylococcus (staph infections) 56
- 57. Gram Negative Bacteria • Thin layer of peptidoglycan in cell wall • Extra thick layer of lipids • Stain pink or reddish • Hard to treat with antibiotics • Some photosynthetic but make sulfur not oxygen • Some fix nitrogen for plants 57
- 58. Gram Negative • Rhizobacteria grow in root nodules of legumes (soybeans, peanuts) • Fix N2 from air into usable ammonia 58
- 59. Gram Negative • Rickettsiae are parasitic bacteria carried by ticks • Cause Lyme disease & Rocky Mountain Spotted Fever 59
- 60. Cyanobacteria • Gram negative • Photosynthetic • Called blue-green bacteria • Contain phycocyanin (red- blue) pigments & chlorophyll 60
- 61. Cyanobacteria • May be red, yellow, brown, black, or blue-green • May grow in chains (Oscillatoria) • Have Heterocysts to help fix N2 • First to re-enter devastated areas • Some cause Eutrophication (use up O2 when die & decompose in water) 61
- 62. Cyanobacteria 62
- 63. Spirochetes • Gram positive • Flagella at each end • Move in corkscrew motion • Some aerobic; others anaerobic • May be free living, parasitic, or symbiotic 63
- 64. Enteric Bacteria • Gram negative • Can live in aerobic & anaerobic habitats • Includes E. coli in intestines • Salmonella – causes food poisoning 64
- 65. Chemoautotrophs • Gram negative • Obtain energy from minerals like iron • Found in freshwater ponds 65
- 66. Nutrition, Respiration, and Reproduction 66 66
- 67. Modes of Nutrition • Saprobes – feed on dead organic matter • Parasites – feed on a host cell • Photoautotroph – use sunlight to make food • Chemoautotroph – oxidize inorganic matter such as iron or sulfur to make food 67
- 68. Methods of Respiration • Obligate Aerobes – require O2 (tuberculosis bacteria) • Obligate Anaerobes – die if O2 is present (tetanus) • Facultative Anaerobes – don’t need O2, but aren’t killed by it (E. coli) 68
- 69. Bacterial Respiration • Anaerobes carry on fermentation • Aerobes carry on cellular respiration 69
- 70. Reproduction • Bacteria reproduce asexually by binary fission • Single chromosome replicates & then cell divides • Rapid • All new cells identical (clones) 70
- 71. Cellular organism copies it’s genetic information then splits into two identical daughter cells 71
- 72. Binary Fission E. coli 72
- 73. Reproduction • Bacteria reproduce sexually by Conjugation • Form a tube between 2 bacteria to exchange genetic material • Held together by pili • New cells NOT identical 73
- 74. Conjugation 74
- 75. Spore Formation • Form endospore whenever when habitat conditions become harsh (little food) • Able to survive for long periods of time as endosperm • Difficult to destroy (heat resistant) 75
- 76. Transduction & Transformation • Genetically change bacteria • May become antibiotic resistant • Transformed bacteria pick up pieces of DNA from dead bacterial cells • Transduction – viruses carry foreign DNA to bacteria; used to make insulin 76
- 77. Pathenogenic Bacteria 77 77
- 78. Pathogens • Called germs or microbes • Cause disease • May produce poisons or toxins • Endotoxins released after bacteria die (E. coli) • Exotoxins released by Gram + bacteria (C. tetani) 78