Ch.6 Microbial Growth Flashcards
what are the physical requirements for growth?
temp, pH, osmotic pressure
what is the optimal temp for psychrophiles ?
0 to 20-25 C
what is the optimal temp for mesophiles ?
37 C
what’s the optimal temp for thermophiles?
40 to 75-80 C
what is the optimal temp for hyperthermophiles?
> 80 C
what happens in a HYPERtonic solution?
water exits the cell
plasmolysis occurs(shrinkage of cytoplasm)
what happened in HYPOtonic solution?
water enters the cell
cell swells
what is the pH for acidophiles?
< 6
what is the pH for alkaliohiles?
> 8
what is the range of pH for molds & fungi?
range of 5-6
what are the chemical requirements for growth?
carbon
oxygen
nitrogen
hydrogen
phosphorus
sulfur
potassium
magnesium
calcium
iron
what is chonps?
carbon
hydrogen
oxygen
nitrogen
phosphorus
sulfur
what is life’s molecules mostly comprised of ?
CHONPS
DNA
RNA
Proteins
Lipids
Carbohydrates
what are essential nutrients?
nutrients that cannot be synthesized and must be supplied other waste growth ceases
what are the required micronutrients?
Co
Cu
Mn
Mo
Ni
Z
what are the organic growth factors?
vitamins
amino acids
blood
serum
what neutralizes the affect of O2 radicals?
Superoxide dimutase
where is SOD found?
found in aerobes, aerotolerant aerobes, facultative anaerobes
what does catalase and peroxidase do?
neutralize peroxide anion (O262-) found in H2O2
what are aerobes?
are aerobic respires that use O2
what can aerobes be?
obligate aerobe
Microaerophile
what is an anaerobe?
they do not use O2
they ferment or respire anaerobically