1 / 59

BACTERIA

BACTERIA. BACTERIA. are microscopic prokaryotes .  (“before nucleus ”) they are adapted to living in all environments – they exist EVERYWHERE. Bacteria are classified into two kingdoms :. Eubacteria (true bacteria ) The larger kingdom Huge variety

menefer
Download Presentation

BACTERIA

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. BACTERIA

  2. BACTERIA • are microscopic prokaryotes.  (“before nucleus”) • they are adapted to living in all environments – they exist EVERYWHERE

  3. Bacteria are classified into two kingdoms: • Eubacteria(true bacteria) • The larger kingdom • Huge variety • Have a Cell wall has peptodoglycan(a carbohydrate) and a cell membrane so are very resistant to damage • 2. Archaebacteria (Ancient Bacteria) • no peptodoglycan in the cell walls • often found in harsh environments • some key DNA sequences resemble • eukaryotes

  4. a. The cell wall may be surrounded by an organized capsule called a glycocalyx and/or by a loose gelatinous sheath called a slime layer. b. In parasitic forms, these outer coverings protect the cell from host defenses. 1. Outside the plasma membrane of most cells is a rigid cell wall that keeps the cell from bursting or collapsing due to osmotic changes by peptidoglycan, a complex molecule containing a unique amino disaccharide and peptide fragments. 

  5. 2. Flagella is used for movement 3.  Pilli (Fimbrae) help bacteria cling to surfaces 4. Prokaryotes do not have organelles or a membrane bound  nucleus! I. Bacteria Structure 5.  Nucleoid region contains a circular loop of DNA 6.  Plasmids are rings of DNA, used in reproduction 7.  Ribosomesin cytoplasm synthesize proteins

  6. Cell Membrane – regulates what comes in and out of the cell Cell Wall – maintains shape and form Capsule – found in virulent bacteria, helps evade immune system

  7. II.  Reproduction in Prokaryotes Binary fission is the splitting of a parent cell into two daughter cells; it is asexual reproduction in prokaryotes. I

  8. In bacteria, genetic recombination can occur in three ways. a. Conjugation occurs when a bacterium passes DNA to a second bacterium through a tube (sex pilus) that temporarily joins two cells; this occurs only between bacteria in the same or closely related species. b.Transformationinvolves bacteria taking up free pieces of DNA secreted by live bacteria or released by dead bacteria. c. In transduction,bacteriophages transfer portions of bacterial DNA from one cell to another. Plasmids can carry genes for resistance to antibiotics and transfer them between bacteria by any of these processes

  9. Plasmid – an extra bit of DNA, used in sexual reproduction conjugation Plasmids are also used in genetic engineering

  10. TRANSFORMATION

  11. III.  Prokaryotic Nutrition 1.   Bacteria differ in their need for, and tolerance of, oxygen (O2). a.   Obligate anaerobes are unable to grow in the presence of O2; this includes anaerobic bacteria that cause botulism, gas gangrene, and tetanus. staphylococcus is a gram-positive, facultative anaerobe b.   Facultative anaerobes are able to grow in either the presence or absence of gaseous O2. c.   Aerobic organisms (including animals and most prokaryotes) require a constant supply of O2 to carry out cellular respiration.

  12. 2.   Autotrophic Prokaryotes a.   Photoautotrophs are photosynthetic and use light energy, water and CO2 to assemble the organic molecules they require. b.   Chemoautotrophsalso use CO2 and make organic molecules but use energy from enviromental chemical reactions involving ammonia, sulfur, iron, etc. (methanogens)

  13. THERMOACIDOPHILE – the red stuff on the rocks This is an archaebacteria. THE FUTURE BELONGS TO ARCHAE!

  14. 3.Heterotrophic Prokaryotes a. Most free‑living bacteria are chemoheterotrophstake in organic nutrients for energy and carbon. b.    There is probably no natural organic molecule that cannot be broken down by some prokaryotic species. c.    Detritivores (saprophytic bacteria)are critical in recycling materials in the ecosystem; they decompose dead organic matter and make it available to photosynthesizers. Bacteria have an important role to play in breaking down materials in the environment. Some are harmful and break down material we'd rather keep, like this image of an infection of necrotizing fasciitis (flesh-eating bacteria)

  15. IV. Bacteria Shape & Naming Bacteria Shapes Cocci – spheres Bacilli – rods Spirilla - spirals

  16. Staph – in clusters Strep – in chains Streptococcus

  17. The Gram stain procedure (developed in the late 1880s by Hans Christian Gram) differentiates bacteria.a. Gram‑positive bacteria stain purple, whereas Gram‑negative bacteria stain pink.b. This difference is dependent on the thick or thin (respectively) peptidoglycan cell wall. Gram staining

  18. Gram Stain Procedure

  19. Gram Negative

  20. Gram Positive

  21. Identify

  22. Identify Gram Negative, Bacillus

  23. Identify

  24. Gram Positive, Bacillus (Anthrax)

  25. Identify

  26. Identify Gram Positive Staphylococcus

  27. Bacteria and You You will be viewing many types of bacteria with slides and slide viewers.  Your main task is to identify by shape and gram stain.   You will also need to know specific names (and appearance) of bacteria that cause disease in humans. *Don't forget, you can review this presentation online anytime.

  28. Identify These Strains are responsible for strep throat, and flesh eating bacteria

  29. Streptococcus These Strains are responsible for strep throat, and flesh eating bacteria

  30. Staphylococcus aureus Staph means “bunch of grapes” in greek.

  31. Staph Infection

  32. Bacillus subtilis Easy to grow in the lab, not harmful Gram Positive *this is an example of a "poor" stain, it looks both pink and purple.  Gram staining takes practice

  33. Tetanus Rigid muscles from tetanus infection Also known as “lockjaw”

  34. Clostridium botulism Gram positive Causes food poisoning that is sometimes fatal All forms lead to paralysis that typically starts with the muscles of the face and then spreads towards the limbs.[1] In severe forms, it leads to paralysis of the breathing muscles and causes respiratory failure. In view of this life-threatening complication, all suspected cases of botulism are treated as medical emergencies, and public health officials are usually involved to prevent further cases from the same source.[1]

  35. A form of botulism is used in BOTOX treatments, as it paralyzes the muscles of the face and effectively smooths wrinkles. Results may vary.

  36. Yersinia Pestis The black plague, this bacteria was carried on the fleas of rats.  It was responsible for the deaths of thousands of Europeans from the 8th to the 14th century.

  37. Bacillis Anthracis (Anthrax)

  38. Bacillus (unknown strain)

  39. Mycoplasmas Causes pneumonia Rickettsia rickettsi Rocky Mountain Spotted Fever, carried by ticks

  40. E. Coli

  41. Spirilla Bacteria

  42. Salmonella

  43. Name this Bacteria

  44. Name this Bacteria Answer: Staphylococcus

  45. Plush Germs Syphilis E. Coli

  46. Gonorrhea The Plague (Black Death)

  47. V. Culturing Bacteria

More Related