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what is a psychrophile?
cold loving microbe
what is a mesophile
a moderate tempurate loving microbe
what is a thermophile
a heat loving microbe
what is the minimum growth tempurature
lowest tempurature at which a cell will grow
what is optimimum growth tempurature?
the tempurature at which species grows the best
maximum growth tempurature is
the highest tempurature at which the growth is possible
can grow at 0 degrees celcius but not about 40 degrees- grow well at refridgerator tempuratures
a hyperthermophile grows at tempuratures of ____ or more and can be also called
80 degrees c and extreme thermophiles
acidophiles are ____loving microbes.
The osmotic loss of water is called ____________ (shrinking of cells cytoplasm)
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
most bacteria grow best at a pH of ___ and ___
1. all organs require a _______source.
2. chemoautotrophs use an _______molecule and autotrophs typically use _________ _______.
- 1. Carbon
- 2. organic, carbon dioxide
_________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.
- and nitrogen fixation AKA N2
Microbes that use molecular oxygen are called what?
organisms that require oxygen to live are known as?
Facultative anaerobes can use _____when its present, but then able to survive and continue growth by fermentations or anaerobic respiration when ______is not available/
Obligate anaerobes are unable to use oxygen for _____ _____ ______, and infact are harmed by it/
energy yielding reactions.
areotolerant anaerobes cannot use _______for growth but can tolerate it fairly well.
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
Chemical Requirments for microbial growth are :
1. most important: Carbon, Nitrogen, Oxygen,2. other still important trace elements: sulfur, phosphorus,
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. A ________ ________ medium is one in which the exact chemical composition is known.
1. A complex medium is one in which the exact chemical composition ___ _____ _______.
is not known
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
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.
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.
1. An _______ culture is used to encourage the growth of a particular microorganism in a mixed culture.
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. Microbes can be preserved for long periods of time by deep-freezing or ________________
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
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
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
- 3. stationary
- 4. death
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
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.
The most probable number (MPN) method can be used for microbes that will grow in ______ _______; it is a statistical estimation.
1. liquid medium
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
1. A spectrophotometer is used to determine _______ by measuring the amount of light that passes through a suspension of cells.
2. An indirect way of estimating bacterial numbers is measuring the ________ _______ of the population, for example, acid production or oxygen consumption.
3. For filamentous organisms such as fungi, measuring dry weight is a convenient method of ________________