In a bacterial growth curve, the period in which maximum cell size is obtained is_____
Bacterial Growth Curve: The bacterial growth curve shows the following four distinct phases - 1) Lag phase: Bacteria adapt to their new environment. Enzymes and intermediates are formed and accumulate until they are present in concentrations that permit growth to resume. Bacterial cell size is maximum in end of the lag phase. It is Preparatory phase Accumulation of enzymes and metabolites 2. Log or Exponential Phase: 3. Stationary phase: The bacterial growth almost stops completely due to lack of essential nutrients, lack of water oxygen, change in pH of the medium, etc. and accumulation of their own toxic metabolic wastes. Death rate of bacteria equals the rate of replication of bacteria. Endospores sta forming during this stage. Many bacteria sta producing exotoxins. Bacteria become Gram variable and show irregular staining. 4. Decline phase: During this phase, the bacterial population declines due to death of cells. The decline phase stas due to - Accumulation of toxic products and autolytic enzymes and Exhaustion of nutrients. Involution forms are common in this stage.
Beginning of Lag phase
End of lag phase
Beginning of stationary phase
Log phase
General Microbiology Pa 1 (History, Microscopy, Stains and Structure and Physiology of Bacteria)