Lag phase- A period of inoculation of the bacteria cells. They acclimatise here and no growth is observed.
Log phase- Bacteria cells begin to grow as their growth enzymes are being activated here. Growth is maximum in this phase.
Steady/maturation phase- Growth rate equals death rate here. This arises due to the accumulation of toxins. Growth here is slow.
Diminishing phase. Here the death rate is more than the growth rate. With time, growth rate becomes nullified and the bacteria cells become non viable, that is, they die.
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