Term
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Definition
Multiplying process generally used by prokaryotes
Increase is exponential |
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Term
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Definition
| An increase in the number of cells in a population |
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Term
| Generation or doubling time |
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Definition
| The time it takes for a population to double in number |
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Term
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Definition
Number of cells in a population at given time-Nt
Original number of cells in population- N0
the number of divisions those cells have undergone during that time- (n) |
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Term
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Definition
Polysaccharide-encased communities
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Term
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Definition
Where prokaryotes are isolated & grown in order to identify and study the activities of a particular spp
Defined as population of organisms descended from a single cell & therefore seperated from all other spp |
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Term
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Definition
Free of microbes prior to use
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Term
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Definition
| Procedures that minimize the chance of other organisms being accidentally introduced |
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Term
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Definition
| The medium that cells are grown in or on, is a mixture of nutrients dissolved in water & may be in a liquid broth or a solidified gel-like form |
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Term
| Basic requirements for obtaining a pure culture |
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Definition
| Solid culture medium, media container that can be maintained in an aseptic condition & a method to seperate individual bacterial cells |
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Term
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Definition
A mass of cells descendd from the original one
About 1 million cells required to be visible by naked eye |
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Term
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Definition
Polysaccharide extracted from marine algae
Used to solidify a liquid culture medium
Very few bacteria can degrade
Not destroyed at high temp |
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Term
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Definition
| 2 part covered container made of glass or plastic |
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Term
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Definition
| Technique for isolating bacteria |
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Term
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Definition
A culture stored for use as an inoculum in later procedures
Often stored in refrigerator as growth on agar slant |
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Term
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Definition
| Agar medium in a tube that was held at a shallow angle as the mefium solidified, creating a larger surface area |
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Term
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Definition
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Term
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Definition
When bacteria is grown in broth contained in a tube or flask or an agar plate
Nutrients are not renewed nor waste products removed
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Term
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Definition
| Pattern of stages the population in a closed system grows |
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Term
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Definition
| Gathering energy in the form of ATP in order to multiply in the next stage |
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Term
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Definition
| Cells divide at a constant rate & their numbers increase by the same percentage during each time interval |
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Term
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Definition
Total # of viable cells in overall population remain relatively constant
Some cells are dying while others are multiplying |
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Term
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Definition
| When total # of viable cells in the population decreases as cells die off at a constant rate |
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Term
| Phase of prolonged decline |
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Definition
Very gradual decrease in the number of viable cells in the population
(march towards death) |
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Term
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Definition
| Device continuously drips fresh medium into a liquid culture contained in a growth chamber |
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Term
| Extremophiles (domain archaea) |
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Definition
| Prokaryotes that can live in harsh enviroments & would kill most other organisms |
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Term
| Environental factors that influence mocrobial growth |
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Definition
Temperature
Amount of oxygen
pH
Water availability |
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Term
| Optimum growth temperature |
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Definition
| The temperature at which the organism multiplies most rapidly |
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Term
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Definition
| Containing little to no oxygen (stomach & intestines) |
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Term
Obligate aerobes
Obligate anaerobes
Facultative anaerobes
Microaerophiles
Aerotolerant aerobes |
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Definition
Have a requirement for oxygen
Cant multiply if oxygen is present
Grow better if present but not required
Requires small amounts of oxygen for aerobic respiration
Can grow in present but do not use to transform energy |
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Term
Super-oxide O2-
Hydrogen peroxide H2O2 |
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Definition
Produced as both a part of normal metabolic processes & as chemical reactions involving oxygen
Result from metabolic processes involving oxygen |
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Term
Superoxide dismutase
Catalese |
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Definition
degrades superoxide to produce H2O2
Breaks down hydrogen peroxide to H2O & O2 |
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Term
Neutrophiles
Acidophiles
Alkalophiles |
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Definition
Bacteria that can live & multiply w/n the range of pH 5- pH 8 & have a pH optimum near neutral
Grow optimally at a pH below 5.5
Grow optimally at a pH levow of 8.5+ |
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Term
Halotolerant
Halophiles
Extreme halophiles |
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Definition
Bacteria that can tolerate high salt concentration (app 10%)
Organisms that require a high sodium chloride level
Require 9% + of sodium chloride |
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Term
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Definition
Concentrates the bacteria by filtration before they are plated
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