Microbial Growth

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Microbial Growth
2012-10-14 01:13:54

microbes and what they do or do not need to thrive
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  1. what is a psychrophile?
    cold loving microbe
  2. what is a mesophile
    a moderate tempurate loving microbe
  3. what is a thermophile
    a heat loving microbe
  4. what is the minimum growth tempurature
    lowest tempurature at which a cell will grow
  5. what is optimimum growth tempurature?
    the tempurature at which species grows the best
  6. maximum growth tempurature is
    the highest tempurature at which the growth is possible
  7. phsycrotrophs are
    can grow at 0 degrees celcius but not about 40 degrees- grow well at refridgerator tempuratures
  8. a hyperthermophile grows at tempuratures of ____ or more and can be also called
    80 degrees c and extreme thermophiles
  9. acidophiles are ____loving microbes.
  10. The osmotic loss of water is called ____________ (shrinking of cells cytoplasm)
  11. 1.Microorganism that have adapted and require salt for growth are called?
    2. organisms that cannot survive without high salt concentrations are called?
    3.organisms that do not require salt for growth but can grow at salt concentrations up to 2 % are called
    • 1.extreme halophiles.
    • 2. obligate  halophiles.
    • 3.facultative halophiles
  12. most bacteria grow best at a pH of ___ and ___
    6.5  7.5
  13. 1. all organs require a _______source.
    2. chemoautotrophs use an _______molecule and autotrophs typically use _________ _______.
    • 1. Carbon
    • 2. organic, carbon dioxide
  14. _________is needed for protien and nucliec acid synthesis. It can be obtained from decomposition of protiens or from NH4+ or NH3-. Only are cabable of this kind of fixation.
    • Nitrogen
    • and nitrogen fixation AKA N2
  15. Microbes that use molecular oxygen are called what?
    organisms that require oxygen to live are known as?
    • Aerobes
    • Obligate aerobes
  16. Facultative anaerobes can use _____when its present, but then able to survive and continue growth by fermentations or anaerobic respiration when ______is not available/
    Oxygen oxygen
  17. Obligate anaerobes are unable to use oxygen for _____ _____ ______, and infact are harmed by it/
    energy yielding reactions.
  18. areotolerant anaerobes cannot use _______for growth but can tolerate it fairly well.
  19. What is a microaerophile?
    these are aerobic, still require oxygen but only grow in oxygen concentrations lower than those in the air. do not grow near surface of solution
  20. Chemical Requirments for microbial growth are :
    1. most important: Carbon, Nitrogen, Oxygen,2. other still important trace elements: sulfur, phosphorus,
  21. 1.  A culture medium is any material prepared for the ___ of bacteria in a laboratory
    .2.  Microbes that grow and multiply in or on a culture medium are known as a ______
    .3.  \_____ is a common solidifying agent for a culture medium.
    • 1. growth
    • 2.culture
    • 3.agar
  22. 1.  A ________   ________ medium is one in which the exact chemical composition is  known.
    chemically defined
  23. 1.  A complex medium is one in which the exact chemical composition ___    _____   _______.
    is not known
  24.  1.  Reducing media chemically removes _____ ______ that might interfere with      the growth of anaerobes.
    2.  _____ plates can be incubated in an anaerobic jar or anaerobic chamber.
    • 1. Molecular oxygen or 02
    • 2.Petri
  25. 1.  Some _______ and ______ bacteria must be cultured in living animals or in cell      cultures
    2.  CO2 incubators or candle jars are used to grow bacteria requiring an increased ______concentration.  These bacteria are referred to as ______.
    • 1. Parasitic and fastidious
    • 2. CO2 and capnophiles.
  26. 1.  By inhibiting unwanted organisms with salts, dyes, or other chemicals, _______  media allow growth of only the desired microbes.
    2.  Differential media are used to distinguish among _______   _________.
    • 1. Selective
    • 2. different organisms.
  27.  1.  An _______ culture is used to encourage the growth of a particular microorganism      in a mixed culture.
  28. 1.  A _____ is a visible mass of microbial cells that theoretically arose from one cell.
    2.  Pure cultures are usually obtained by the ______  _____method. 
    • 1. colony
    • 2. streak plate
  29. 1.  Microbes can be preserved for long periods of time by deep-freezing or ________________
    lyophilization      (freeze-drying).
  30. 1.  The normal reproductive method of bacteria is by ______  _______, in which a single cell      divides into two identical cells.
    2.  Some _______ reproduce by budding, aerial spore formation, or fragmentation. 
    • 1. binary fission
    • 2.bacteria
  31.  1.  The time required for a cell to divide or a population to double is known as the ______  ________.
    2..  Bacterial division occurs according to a ________process (2 cells, 4 cells, 8 cells,      etc.). 
    • 1. generation time
    • 2.logarithmic
  32. 1.  During the ___ phase, there is little or no change in the number of cells, but metabolic activity is high.
    2.  During the___ phase, the bacteria multiply at the fastest rate possible under the conditions provided.
    3.  During the ______ phase, there is and equilibrium between cell division and death.
    4.  During the _____ phase, the number of deaths exceeds the number of new cells  formed.
    • 1. lag
    • 2.log
    • 3. stationary
    • 4. death
  33. 1.  A ______  _____ _____reflects the number of viable microbes and assumes that each bacterium grows into a single colony; plate counts are reported as number of colony- forming units (CFU).
    2.  A plate count may be done either by the____plate method or the _____ plate method.
    • 1. standard plate count
    • 2.pour plate or spread plate
  34. 3.  In _______ bacteria are retained on the surface of a membrane filter and then  transferred to a culture medium to grow and subsequently be counted.
  35. The most probable number (MPN) method can be used for microbes that will grow in  ______  _______; it is a statistical estimation.
    1. liquid medium
  36. In a direct microscopic count, the microbes in a measured volume of a_________ ________ are counted with the use of a specially designed slide.
    1, bacterial suspension
  37. 1.  A spectrophotometer is used to determine _______ by measuring the amount of light      that passes through a suspension of cells.
  38. 2.  An indirect way of estimating bacterial numbers is measuring the ________ _______ of  the population, for example, acid production or oxygen consumption.
    metabolic activity
  39. 3.  For filamentous organisms such as fungi, measuring dry weight is a convenient      method of ________________
    growth measurement