Ce diaporama a bien été signalé.
Nous utilisons votre profil LinkedIn et vos données d’activité pour vous proposer des publicités personnalisées et pertinentes. Vous pouvez changer vos préférences de publicités à tout moment.

Bacteria Power Point

27 812 vues

Publié le

Publié dans : Technologie, Santé & Médecine
  • Soyez le premier à commenter

Bacteria Power Point

  1. 1. Bacteria Chapter 21
  2. 2. Bacteria are VERY small! http://mrbarlow.files.wordpress.com/2008/10/bacteria-on-a-pin.jpg
  3. 3. Euglena 100 µm Plant cell 35-80 µm Animal cell 5-30 µm Spirocheta 10 µm Bacteria are small compared to cells with nuclei Virus 20-200 nm
  4. 4. Bacteria compared to white blood cell that will eat it!
  5. 5. Key Concepts about Bacteria <ul><li>Kingdom Monera </li></ul><ul><li>Prokaryote=no nucleus or internal compartments </li></ul><ul><li>All are single cells </li></ul><ul><li>Single circular piece of DNA </li></ul>http://micro.magnet.fsu.edu/cells/procaryotes/images/procaryote.jpg
  6. 6. Structure of Bacteria Carries genetic information. It is circular Chromosome Contains DNA, ribosomes, essential compounds Cytoplasm Regulates movement of materials, contains enzymes important to cellular respiration Cell Membrane Protects against antibodies Outer Membrane Protects and gives shape Cell Wall Function Structure
  7. 7. Structure of Bacteria Contains some genes obtained through recombination Plasmid Protects the cell and assist in attaching cell to other surfaces Capsule & Slime Layer Protects cell against harsh environments Endospore Assists the cell in attaching to other surfaces Pilus Moves the cell Flagellum
  8. 8. Shapes- How bacteria are identified! <ul><li>Bacilli- rod shaped </li></ul><ul><li>Spirilla- spiral shaped </li></ul><ul><li>Cocci- sphere shaped </li></ul><ul><ul><li>Staphylococci- grape-like clusters </li></ul></ul><ul><ul><li>Streptococci- in chains </li></ul></ul>
  9. 9. Bacillus bacteria are rod shaped
  10. 10. Spirillium bacteria have a corkscrew shape
  11. 11. Coccus bacteria are sphere or ball shaped
  12. 12. Staphylobacteria occur in clumps, such as this staphylococcus bacteria that cause common infections of cuts
  13. 13. Diplo-bacteria occur in pairs, such as the diplococcus bacteria
  14. 14. Streptobacteria occur in chains, like this streptococcus bacteria
  15. 15. Bacterial Reproduction: Binary Fission
  16. 16. Conjugation <ul><li>Genetic information transferred on plasmids - and sometimes antibiotic resistance </li></ul>
  17. 17. Nutrition and Growth <ul><li>Autotroph- producer, makes energy from environmental sources </li></ul><ul><ul><li>Chemoautotrophs- Take Hydrogen from NH 3 or H 2 S and oxidize it using the energy to make amino acids and proteins </li></ul></ul><ul><ul><li>Photoautotrophs- photosynthetic- Uses sunlight for energy </li></ul></ul>
  18. 18. Nutrition and Growth <ul><li>Heterotroph- feed on organic material formed by other organisms </li></ul><ul><ul><li>Decomposers </li></ul></ul><ul><ul><li>Secrete enzymes in their organic environment and then absorb the nutrients </li></ul></ul><ul><ul><li>They can metabolize their host </li></ul></ul>
  19. 19. Endospores <ul><li>Some bacteria can form endospores, which are non-replicative cell forms that are highly resistant to environmental factors. </li></ul>Endospore
  20. 20. Gram Stain- Another way to identify Bacteria Purple= Gram Positive Pink= Gram Negative
  21. 21. Bacterial Cell Walls <ul><li>Peptidoglycan is the material that makes up bacterial cell walls </li></ul>Thicker peptidoglycan layer but not outer membrane means gram + Thinner peptidoglycan layer with an outer membrane means gram -
  22. 22. How do Bacteria cause disease? <ul><li>Metabolize their host for food (Heterotrophic bacteria) </li></ul><ul><li>Secrete a toxin which can attack other body parts (Botulism is an example) </li></ul><ul><li>Contain an endotoxin in their cell wall which is released when the bacterium dies. An example of this is salmonella. </li></ul>
  23. 23. How can Bacteria work to our benefit? <ul><li>Digest waste at sewage plants </li></ul><ul><li>Chemical industry- make acetone and butanol </li></ul><ul><li>Pharmaceutical- vitamins, antibiotics, insulin </li></ul><ul><li>Food- yogurt, cheese, alcoholic beverages </li></ul><ul><li>Decomposer </li></ul><ul><li>Nitrogen fixers </li></ul><ul><li>Symbiosis </li></ul>

×