Bacterial growth curve
During the bacterial growth cycle bacterial cell divide by binary fission and their mass , numbers increase in an exponentially with time . When bacteria are grown is a suitable liquid medium and incubated . When a graph plot between the growth of bacteria and time phage is known as growth curve
Bacterial growth curve has four phase
1- LAG PHASE
2-LOG PHASE /EXPONENTIAL PHASE
3-STATIONARY PHASE
4-DECLINE PHASE /DEATH PHASE
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| Bacterial growth curve |
1- LAG PHASE
At this phase ,the cell increase in size but not increase in numbers
During this phase,
✓Bacterial metabolism increase
✓Adapted themselves in the new climates
✓Synthesizing of DNA , Enzymes and other components needed for cell division
2-LOG PHASE
This phase also known as Exponential phase
In this phase ,
∆ Bacteria starts cell dividing
∆ Bacterial cell increase in numbers
∆ Bacteria have high rate of metabolism
In this phase their are maximum growth of bacteria bcoz after germination of bacteria they reproduce in fast rate and bacteria increase cells in numbers bcoz nutritions are more than the bacteria . So bacteria grow maximum in numbers
3-STATIONARY PHASE
In this phase after sometime a stage comes when rate of multiplication of cell and that becomes almost equal due to
✓ Depletion of nutrients
✓ Accumulation of toxicity
4-DECLINE PHASE
During this phase bacterial population decline/decrease due to death of cells.
✓It is due to accumulate toxic (waste products) on nutrients agar plate.
✓Lacking of nutrients agar media
