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  1. the cell envelope
    external covering outside the cytoplasm
  2. what are the 2 basic layers the cell envelope is composed of
    • cell wall-outer
    • cell membrane -inner
  3. what does the cell envelope do
    maintain cell integrity
  4. gram positive bacteria
    thick cell walls composed primarily of peptidoglycan and cell membrane
  5. gram negative bacteria
    outer membrane, thin peptidoglycan layer, and cell membrane
  6. structure of cell walls
    determines cell shape, prevents lysis or collapsing due to changing osmotic pressures
  7. peptidoglycan
    • unique macromolecule composed of a repeating framework of long glycan (sugar) chains cross linked by short peptide (protein) fragments
    • makes up bacterial cell walls
  8. what is the outer membrane similar to
    cell membrane bilayer structure
  9. what does the outermost layer contain in the gram negative cell wall and what are they
    • lioppolysacchardes and lipoprotein (LPS)
    • which are endotoxins that may become toxic when released during infection
  10. what is the bottom layer composed of in the gram negative cell wall
    phospholipids and lipoproteins
  11. what surrounds the peptidoglycan
    periplasmic space
  12. what are gram stain
    • differential stain that distinguishes cells with a gram positive cell wall from those with gram negative cell walls
    • *important basis of bacterial classification and identification
    • *practical aid in diagnosing infection and guiding drug treatment
  13. what color do gram positive turn
    retain crystal violet and stain purple
  14. what color do gram negative turn
    lose crystal violets and stain red from safranin counterstain
  15. atypical cell walls
    • bacterial groups that lack cell wall structure (mycobacterium)
    • stain gram + but are not they contain lipid mycolic acid
    • some have no cell wall (mycoplasma)
    • cell membrane is stabilized by sterols
    • pleomorphic
  16. pleomorphic
    having extreme variation in shape
  17. what is the cell membrane structure
    phospholipid bilayer with embedded proteins-fluid mosaic model
  18. what does the cell membrane function in
    • providing site for energy reaction, nutrient processing, and synthesis
    • transport into and out of cell (semi permeable)
  19. cytoplasm
    • dense gelatinous solution of sugar, amino acids, and salt
    • 70-80% water
    • aka cytosol
  20. chromosomes
    single, circular, double stand DNA molecules that contains all the genetic information required by a cell
  21. nucleoid
    a dense area where DNA is tightly coiled around a protein
  22. plasmids
    • small circular double stranded DNA
    • duplicated and passed on to offspring
    • not essential to bacterial growth and metabolism
    • used in genetic engineering- manipulated and transferred from cell to cell
  23. inclusions and granules
    • intracellular nutrients storage bodies
    • vary in size, number and content
    • bacterial cells use them when environmental sources are depleted
  24. what are the 3 types of endospores
    • dormant
    • sporulation
    • germination
  25. dormant endospores
    • resting,cells produced by some G+ bacteria
    • have two phases
    • vegetative cell and endospores
  26. vegetative cell
    • metabolically active and growing
    • can reproduce in this stage
  27. endospore (dormant)
    • when exposed to adverse environmental conditions capable if high resistance and very long term survival
    • cant reproduce in this stage
  28. what are clostridium, bacillus and sporosarcina
    dormant endospores
  29. sporulation
    • formation of endospores
    • hardiest of all life form
    • withstands extreme in heat, drying, freezing, radiant, and chemicals
    • not a means of reproduction
  30. germination
    return to vegetative growth
  31. endospores
    • thick coat
    • resistant to ordinary cleaning methods and boiling
    • pressurized steam and 120 C for 20-30 min will destroy (autoclave)
    • produced by several bacterial pathogens
  32. what are the bacterial pathogens that produce endospores
    • bacillus anthracis (cause of anthrax-candidate for bioterrorism) (Robert Koch)
    • clostridium tentani (cause tetanus(lockjaw))
    • clostridium perfringes (causes gas gangrene)
    • clostrium botulinum (cause botulism, a deadly food poisoning
  33. what are the 3 basic shapes of bacteria
    • coccus
    • bacillus
    • spirillum
  34. coccus
    • spherical round
    • cocci
  35. bacillus
    • rod/bacilli
    • coccobacillus-very short and plump rod
    • vibrio-gently curved rods
  36. spirillum
    • rigid helix like cork screw
    • spirilla
    • spirochete-flexible helix, like spring, cant change form can change shape
  37. cocci
  38. diplococci
    in pairs
  39. tetrads
    group of fours
  40. staphylococci or micrococci
    irregular clusters
  41. streptococci
  42. sarcinae
    cubical packets
  43. bacilli
  44. diplobacilli
    in pairs
  45. streptobacilli
  46. palisades
    • rods are parallel
    • "Chinese letter arrangement"
  47. cyanobacteria
    • blue and green algae
    • gram- cell walls
    • have photosynthetic chlorophyll pigments
  48. bacteriochlorophyll
    • green and purple sulfur bacteria
    • do not give off oxygen as a product of photosynthesis
  49. rickettsias
    • very tiny gram- bacteria
    • obligated intracellular pathogens
    • cannot survive or multiply outside of a host
    • cannot carry out metabolism on their own
  50. rickettsia richettisii
    rocky mountain spotted fever
  51. rickettsia prowazekii
    epidemic typhus
  52. clamydias
    • tiny
    • obligate intracellular parasites
    • not transmitted by arthropods
  53. chlamydia trachomatis
    severe eye infection and causes blindness in on the most common sexually transmitted disease
  54. chlamydia pneumoniae
    causes lung infection
  55. archara
    • aka extremophiles
    • live in most extreme habitats in nature
    • adapted to extreme heat cold salt acid and pressure
    • contain unique genetic sequence in their RNA
    • have unique membrane lipids and cell wall constructions
  56. methanogens
    • can produce methane gas
    • common in mud
  57. halophiles
    require salt to grow and can tolerate habitats with extreme salt concentrations
  58. acidophiles
    prefer to live in highly acidic (low ph) environments
  59. barophiles
    can tolerate habitats of extreme pressure
  60. psychrophiles
    • flourish a very low temps
    • found in polar ice caps and snow
  61. hyperthermophiles
    flourish in very high temps like volcanoes
Card Set:
2013-09-16 11:54:10
chapter4 part2

quiz 1
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