Ch. 7.2- Prokaryotic Growth Requirements Flashcards
What does temperature do to growth rates?
Increases enzymes reaction time and increases growth rates. This happens till temp gets too high and proteins denature and cells die.
What bacteria prefer temps at -20 to 10 degrees celsius?
Psychrophiles
They have highly saturated lipids in their cell wall.
What bacteria prefer temps at 0 to 30 degrees celsius?
Psychrotrophs
Associated with food born illness as they live at room temp as well as in refrigerated and frozen temps.
What bacteria prefer temps at 1- to 50 degrees celsius?
Mesophiles
Most pathogens are part of this group as it fits into the range of normal body temperature.
What bacteria prefer 40 to 75 degrees celsius?
Thermophiles
What bacteria prefer 65 to 120 degrees celsius?
Extreme thermophiles
These have adapted proteins to resist high temperatures as well as having chaperones to help refold proteins into their correct stated. They also have adapted cells walls with highly branched and highly saturated lipids.
Define baraphiles
Bacteria that can withstand high pressure environments.
What pH can acidophilus grow at?
1 (or less) to 5- these are often archaea
These usually have a fairly normal cytoplasm pH
What pH can neutraphiles grow in?
5-8
These make up the majority of microorganisms, especially pathogens.
What pH can alkaliphiles grow in?
9-11
What percentage of an environment can be salt while sustaining the life of halophiles?
35%
What is 90% of dehydrated cells made up of?
Carbon, hydrogen, non-gaseous oxygen, and nitrogen
What is the minimum percent of salt that halophiles will tolerate?
2.5%
Define heterotrophs
Microbes that require an external source of carbon like sugars, lipids, and proteins.
Define autotrophs
Self feeding microbes that use carbon fixation to convert inorganic carbon to organic carbon, so they don’t require external sources of organic carbon.
