factor effect growth of microorganism

Light

- active in dark condition; inactive in bright light
- ultraviolet rays able to kill micro n spores.

pH

- active in neutral / near-neutral condit
- acidity / alkalinity kill micro.

Temp

- inactive @ low temp.
- nore active up to abt 40C

the presence of nutrients

- except viruses, all micro need N to live.
- photosynthetic n chemosynthetic micro obtain N in form of minerals.

Humidity

- except viruses, all micro need water to live.
- dry condition, micro become spores n remain inactive until water available.
- micro unable form spores will die off when dry.