Block One Text 6

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Block One Text 6
2014-09-27 17:43:38
Test One
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  1. a.       Both prokaryotes and eukaryotes can bave a __ surrounding them. IN nature, most bacteria are found __ rather than __
                                                                  i.      The __is the glue that holds cells in place
    sticky glycocalyx

    sticking to solid surfaces including other cells rather than free-floating

  2. I.                    Comparing Prokaryotic and Eukaryotic Cells
    • a.       chemically similar in the sense that they both contain nucleic acids, proteins, lipids, and carbohydrates
    •                                                               i.      They use the same kinds of chemical reactions to metabolize food, build proteins, and store energy
  3. Differences
    a.       structure of cell wall and membranes and absence of organelles in prokaryotes
  4. a.       Main differing characteristics of prokaryotes:
    •                                                               i.      Their DNA is not enclosed within a membrane and is usually a singular circularly arranged chromosome
    •                                                             ii.      DNA not associated with histones; other proteins are
    •                                                           iii.      No membrane-enclosed organelles
    •                                                            iv.      Their cell walls have peptidoglycan
    •                                                              v.      Divide by binary fission
  5. a.       Main differing characteristics of eukaryotes: 
    •                                                               i.      DNA in nucleus surrounded by nuclear membrane; DNA found in multiple chromomes
    •                                                             ii.      DNA associated with histones and nonhistones
    •                                                           iii.      Contain membrane-enclosed organelles
    •                                                            iv.      Cell walls, when present, are chemically simple
    •                                                              v.      Cell division involves mitosis
  6. Spherical Cocci

    1.       Usually __ but can be __
    2.       To reproduce, the cells __
    a.       Pair= __
    b.      Those that divide and remain attached in chainlike patterns: __
    c.       Those that divide in two planes nad remain in groups of four are: __
    d.      Those that divide in three planes and remain attached in cubelike groups of eight: __
    e.      Those that divide in multiple planes and form grape
    round but can be oval, elongated, or flattened on one side

    remain attached




  7.                                                               i.      Rod-shaped bacillus
    1.       Most are __
    2.       _are pairs
    3.       __are chains
    4.       Oval shaped, cocci-resembling bacillià __
    single bacilli



  8.                                                               i.      Spiral
    1.       Have __; never straight
    2.       Bacteria that look like curved rods are __
    3.       Others, called __, have a helical shape lke a corkscrew and fairly rigid bodies
    4.       Another group of spirals are helical and flexible; they are called __
    one or more twists



  9.                                                               i.      __, __, and __ also exist
    b.      Shape determined by heredity
                                                                  i.      Most baceeria are __: maintain a single shape
                                                                ii.      Shape can change due to environment or if bacteria is __, having many shapes
    Star-shaped, rectangular, flat cells (halophilic archaea), and triangular cells


  10. I.                    Structures External to the Cell Wall
    a.       External to the prokaryotic cell wall are the glycolayx, flagella, axial filaments, fimbriae, and pili
  11. a.       Glycocalyx: __(means sugar coat)
                                                                  i.      General term used for __
                                                                ii.      Description
                                                              iii.      Chemical comp varies with species
                                                               iv.      Made __
    1.       Firmly attached= __
    2.       Unorganized and loosely attached= __

    substances that surround cells

    Viscous (sticky), gelatinous polymer that is external to the cell wall and composed of polysaccharide, polypeptide, or both

    inside cell and secreted to surface


    slime layer
  12.                                                               i.      Capsules are important in contributing to bacterial virulence because they __
                                                                ii.      Uncapsulated cells are readily __
    protect pathogenic bacteria from phagocytosis by the cells of the host

  13.                                                               i.      Helps cells in a biofilm __ (extracellular polymeric substance), which __, __, ad __
                                                                ii.      Can grow on diverse surfaces
                                                              iii.      Can protect a cell from __; its viscosity may inhibit the movement of nutrients out of the cell
    attach to their target envionrment and to each other

    protects the cells within it, facilitates communication among them, and enables toe cells to surive by attaching to various surfaces in their natural environment

  14. a.       Flagella: __
                                                                  i.      no flagella: __
                                                                ii.      distributed over the entire cell: __
                                                              iii.      __: at one or both poles or ends of the clel
    1.       may be __(a single flagella at one pole), __(a tuft of flagella from one pole), or __(flagella at both poles of the cell)
    long filamentous appendages that propel bacteria

    • atrichous
    • peritrichous
    • polar 
    • monotrichous 
    • lophotrichous 
    • amphitrichous
  15.                                                               i.      three basic parts
    1.       __: long outermost region and contains a globular protein __ arranged in several chains that interwine and form a __ around a __
    2.       in most bacteria, filaments are not covered by a __ or __, but attached to a wider __, with a different protein
    • filament
    • flagellin
    • helix around a hollow core
    • membrane or sheath
    • hook
  16. 1.       the third portion is the __, which __
    a.       small central rod inserted into a series of rings
                                                                                                                                          i.      gram-negative bacteria have __; outer pair is anchored to __, and inner pair of rings is anchored to __
                                                                                                                                        ii.      gram negative: only __ is present
    • basal body
    • anchors the flagellum to the cell wall and plasma membrane
    • two pairs of rings
    • various portions of the cell wall
    • plasma membrane
    • inner pair
  17.                                                               i.      the flagella of eukaryotic cells are __ than prokaryotic cels
    1.       prokaryotic flagellum: movement?
    2.       movement results from __ and is similar to the movement of the shaft of an electric motor
    3.       as the flagella rotate, they __ that pushes against the surrounding liquid and propels the bacteriu
    a.       flagellar rotation depends on the __
    • more complex
    • clockwise or counterclockwise around its long axis
    • rotation of its basal body
    • form a bundle
    • cell’s continuous generation of energy
  18. 1.       Bacterial cells can alter speed and direction of rotation of flagella and care capable of various patterns of __, the ability of an organism to move by itself
    a.       One direction= __, which are interrupeed by abrupt, random changes in direction called “__,” which are caused by__
    b.      __= rapid wavelike movement
    • motility
    • run/ swim
    • tumbles
    •  reversal of flagellar rotation
    • Swarm
  19.                                                               i.      Motility allows bacterium to find favorable environment
    1.       __: movement toward/ away from a stimulus (__)
    2.       Motile bacteria have receptors in various locations that pick up stimuli and pass info to flagella
    a.       Positive chemotactic signal: __
    b.      Negative: __
    3.       The flagellar protein called __ is useful for __
    • Taxis
    • chemotaxis/ phototaxis
    • attractant
    • repellent
    • H antigen
    • distinguishing among serovars, or variations within a species of gram negative bacteria
  20. a.       Axial Filaments
                                                                  i.      __are unique in structure and mobility
    1.       They move by axial filaments (__), which are what?
                                                                ii.      Anchored at one end and have a structure similar to that of flagella
    1.       Rotation produces a movement of the other sheath that propels the spirochetes in a __
    a.       Movement similar to the way a corkscrew moves through a cork
    • Spirochetes 
    • endoflagella
    • bundles of fibrils that arise at the ends of the cell beneath an outer sheath and spiral around the cell
    • spiral motion
  21. a.       Fimbriae and Pili
                                                                  i.      Many gram-negative bacteria have hairlike appendages that are shorter, straighter, and thinner than flagella and used for __ and __ rather than __ .
                                                                ii.      These structures, which consist of a protein called __arranged helically around a __, are divided itno two types, __ and __, having very different functions
    • attachment and transfer of DNA rather than for motility
    • pilin 
    • central core
    • fimbriae and pili
  22.                                                               i.      Can __ or __
                                                                ii.      Adhere to each other and surfacesà help form __ or __
                                                              iii.      Help bacteria adhere to __
    • occur at the poles of the bacterial cell
    • can be evenly distributed over the entire surface of the cell and can be a few or hundreds
    • biofilms and other aggreagges
    • epithelial surfaces
  23.                                                               i.      Pili are __than fimbriae and number __ per cell
    1.       Involved in __ and __
    2.       One type: __— a pilus extends by the addition of subunits of pilin, makes contact with a surface or another cell, and tehn retracts as the pilin subunits are disassembled. This is called a __ and results in short, jerky, intermittent movements
    3.       Other type: __: smooth gliding movement of myxobacteria; some utilize pilus retraction 
    • longer 
    • only one or two
    • motility and DNA transfer
    • twitiching motility
    • grappling hook model of twitching motility
    • gliding motility
  24.                                                               i.      Some pili are used to __, a process called __. Some pili are called __

    • bring bacteria together allowing the transfer of DNA from one cell to another
    • conjugation
    • conjugation (sex) pili
  25. What is the conjugation process?
    • the conjugation pilus of one bacterium called an F+ cell connects to receptors on the surface of another bacterium of its own species or a different species.
    • The two cells make physical contact, and DNA from the F+ cell is transferred to the other cell.
    • The exchanged DNA can add a new function to the recipient cell, such as antibiotic resistance of the ability to digest its medium more efficiently