Physical Requirements
Classifications of Microbes
Bacteria and O2 Relationships
Phases of Bacterial Growth
Bacterial Count
100
Most bacteria grow best between this pH range
What is 6.5 a 7.5
100
"different feeder"
What is heterotroph or organotroph
100
Grow best with low oxygen
What is microaerophile
100
In this phase the population stabilizes
What is stationary phase
100
MPN stands for
What is most probable number
200
These grow best at moderate temperatures that are close to the human body temperature (37 degrees Celsius)
What is mesophiles
200
"chemical feeder"
What is chemotroph
200
Can grow with or without oxygen
What is Facultative anaerobes
200
During this phase microbes are vulnerable to unfavorable conditions
What is log phase
200
This refers to how cloudy a liquid medium becomes as the bacterial cell multipy
What is tubidity
300
The result of the osmotic loss of water
What is plasmolysis
300
"light feeder"
What is phototroph
300
require oxygen
What is obligate aerobes
300
Cells begin to divide, also called the exponential growth phase.
What is log phase
300
This method is used for a small quantity of bacteria, such as a sample of water from a river
What is filtration
400
These grow best under alkaline conditions, usually at a pH of 8
What are alkalophiles
400
"rock feeder"
What is lithotroph
400
Grow without oxygen but not killed by it.
What is aerotolerant anaerobes
400
The phase of little or no cell division
What is lag phase
400
This uses a known volume of bacterial suspension that us placed within a defined area on a microscopic slide
What is direct count
500
These are heat loving microbes
What are thermophiles
500
"self feeder"
What is an autotroph
500
killed by oxygen
What is obligate anaerobes
500
This phase continues until the population has died out completely or only a few living bacterial cells are left
What is death phase
500
The most frequently used method of measuring a bacterial population
What is plate count
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