MICRO Bacteria Food, Oxygen, and Temperature Requirements

Autotrophic bacteria

self-nourishing bacteria.

Heterotrophic bacteria

organisms that must obtain their nourishment from complex organic matter.

Strict (obligate) saprophyte

an organism that can survive only on dead or decaying organic matter.

Strict (obligate) parasite

an organism that is completely dependent on its living host for survival.

Facultative saprophyte

prefers living organic matter as a source of nutrition but can adapt to the use of dead organic matter under certain conditions.

Facultative parasite

prefers dead organic matter as a source of nutrition but can adapt to the use of living organic matter under certain conditions.

Strict (obligate) aerobe

a microbe that can live only in the presence of free oxygen.

Strict (obligate) anaerobe

a microbe that can survive only in the absence of free oxygen.

Microaerophilic

requiring very little free oxygen; as found with certain bacteria.

Facultative aerobes

a microorganism that prefers an environment devoid of oxygen but has adapted so that it can live and grow in the presence of oxygen.

Facultative anaerobes

an organism that prefers the presence of oxygen but is capable of living and growing in its absence.

Minimum temperature

temperature below which bacterial growth will not take place.

Maximum temperature

temperature above which bacterial growth will not take place.

Optimum temperature

temperature at which organisms grow best.

Psychrophile

bacteria that prefer cold, thriving at temperatures between 0 and 25 C.

Mesophile

bacteria that prefer moderate temperatures and develop best at temperatures between 25 and 40C.

Thermophile

bacteria that thrive best at high temperatures, between 40 and 70C.