1 / 25

Classification, Bacteria & Viruses

Classification, Bacteria & Viruses. AP Biology 2010. Systematics. Combination of phylogeny and classification Classification system: Carl Linnaeus Domain, kingdom, phylum, class, order, family genus species Hierarchical; Binomial nomenclature Genus species. Major Lineages of Life.

charleswall
Download Presentation

Classification, Bacteria & Viruses

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. Classification, Bacteria & Viruses AP Biology 2010

  2. Systematics • Combination of phylogeny and classification • Classification system: Carl Linnaeus • Domain, kingdom, phylum, class, order, family genus species • Hierarchical; Binomial nomenclature • Genus species

  3. Major Lineages of Life 3 domains: Bacteria, Eukaryota, Arachae

  4. Prokaryotes: Domains Bacteria & Archae Prokaryotes lack membrane bound organelles (ie. Nucleus, mitochonidria, etc.)

  5. Prokaryotic Cell Structure • Almost all have cell walls. Most contain peptidoglycan (exception: members of Archae) • Gram + : simple cell walls with large amounts of peptidoglycan • Gram - : more complex cell walls with less petidoglycan

  6. Many have capsules and piliand are motile

  7. Prokaryotic Genetic Material & Reproduction • Not in nucleus, concentrated in nucleoid region. • Smaller rings of DNA: plasmids • Reproduce asexually via binary fission • Transformation: can take up genes from surrounding • Conjugation: direct transfer of genes between prokaryotes • Transduction: transfer of genes between prokaryotes via viruses

  8. Bacteriaphage: viruses inject DNA into bacterial cells Binary fission

  9. Conjugation:

  10. Some form endospores: Examples: Clostridium tetani & Clostridium botulinum

  11. Nutritional Diversity • Photoautotrophs: photosynthetic • Chemoautotrophs: use carbon dioxide as carbon source but obtain energy by oxidizing inorganic substances like hydrogen sulfide, ammonia, ferrous iron. • Photoheterotrophs: can use light to generate ATP but need carbon in organic form • Chemoheterotroph: must consume organic molecules for energy and carbon

  12. Metabolic Relationship with Oxygen • Obligate aerobes • Facultative anaerobes • Obligate anaerobes

  13. Archae Extremophiles Thermophiles Halophiles Bacteria Most known bacteria Two prokaryotic domains:

  14. Importance of prokaryotes: • Cyanobacteria: evolution of photosynthesis; transformation of atmosphere • Decomposers • Symbiotic: nitrogen fixation • Biotechnology; bioremediation • Pathogens: • Koch’s postulates • Exotoxins

  15. What spore-forming bacteria has been in the news in recent years? Lungs – severe pneumonia & death Gastrointestinal – vomiting blood, severe diarrhea Cutaneous – necrotic ulcers

  16. Viruses • Can only reproduce within a cell (limited range of host cells) - “hijacks” cell’s nucleic acid and protein synthesis machinery • Protein shell – capsids and some have viral envelopes

  17. Different capsid structures and viral envelope proteins

  18. Bacteriaphage

  19. Lytic life cycle Lysogeneic Life cycle

  20. Host Range • Glycoproteins in viral envelope bind to a cell surface receptor protein on host cell and gains entry into the cell. Example: HIV binds to CD4 receptors of T immune cells

  21. Classes of Viruses • DNA viruses • Retroviruses – RNA (HIV) RNA Reverse transcriptase makes DNA DNA integrates into cell’s genome (provirus)

  22. List of Viruses • HIV • Ebola • Influenza • SARS • Dengue • Hantavirus • Hepatitis • West Nile • Marburg • Lassa • Human monkeypox You will be assigned a virus – make a powerpoint slide about your virus. Include type of virus, method of transmission, incubation, symptoms, treatment, prevention and any other interesting facts

  23. Prevention/Treatment • Vaccines: influenza, polio, measles, mumps, rubella, hepatitis, chicken measles, etc. • Problems with development of HIV vaccine: dead virus does not retain antigenicity, too dangerous to use live attenuated virus. Also highly mutable envelope proteins • Ongoing research with SIV in chimps

More Related