C. Factors That Affect Microbial Growth Flashcards
Facultative
Exist in a wider variety (range of conditions)
Obligate
Exist in a very narrow niche
Cardinal temperature range
Temp range required for growth
Pyschrophile
Grow in cold temperatures
Can grow in 0 C
Mesophile
Optimum temp is 37 C (body temp)
Thermophiles
Exist in hot temp
Ex. Volcano
Extemophiles
Obligate pyschrophile
Only grow in cold
Facultative pyschrophile
Prefer warm
Can grow in cold temp
Growth enzymes
Have specific shapes
Denature when too hot
If an organism uses O2
Toxic waste products will be produced
Need detox enzymes
Two toxic waste products from O2 are?
Superoxide ion
Hydrogen peroxide
2 enzymes that detox
Super oxide dismutase
Catalase
Super oxide dismutase
Converts superoxide ions into hydrogen peroxide
Catalase
Converts hydrogen peroxide into water and oxygen
Obligate aerobe
Must have O2 (or die)
Micro aerophiles
Must have O2, but in smaller concentrations than normal atmosphere
Most of pathogens and normal flora
Obligate anaerobes
Must be in O2 free environment (or die)
Lack detox enzymes
Facultative anaerobes
Can grow in O2 and non O2 environments
Aerotolerant anaerobes
Grow everywhere
Must have detox enzymes
Prefer non - O2
Limited growth in O2
Helicobacter pylori
Bacteria that causes ulcers
It’s an acidophile
Most bacteria are ______, in terms of pH
Neutrophile
Osmotic pressure
Pressure inside the cell from water and solute concentrations
Halophile
Salt lover
Requires a larger amount of salt
Halotolerant
Still grows in a salty environment
The SA / Vol ratio best fit to handle salt water
Large cocci
Osmophile
Grow best in best in environments that are high in sugar
Xerophyte
Grow in dry conditions
