What is the second phase of bacterial growth?

Bacterial colonies progress through four phases of growth: the lag phase, the log phase, the stationary phase, and the death phase. The generation time, which varies among bacteria, is controlled by many environmental conditions and by the nature of the bacterial species.

What is the second phase of growth?

G2 phase, Gap 2 phase, or Growth 2 phase, is the third subphase of interphase in the cell cycle directly preceding mitosis. It follows the successful completion of S phase, during which the cell’s DNA is replicated.

What are the two stages of bacteria?

The life-cycle of bacteria consists of two distinct phases. These are the active stage and the inactive, or spore-forming stage. In the active stage, bacteria grow and reproduce.

What are the four stages of microbial growth?

The four phases are lag, log, stationary, and death.

• The Lag Phase.
• The Log Phase.
• Stationary Phase.
• The Death Phase.
• Sustaining Microbial Growth.
• Direct Cell Count.
• Serial Dilution.
• The Most Probable Number.

What is bacterial growth phase?

The bacterial growth curve represents the number of live cells in a bacterial population over a period of time. There are four distinct phases of the growth curve: lag, exponential (log), stationary, and death. The death phase is characterized by an exponential decrease in the number of living cells.

What is stationary phase in microbiology?

Stationary phase is the stage when growth ceases but cells remain metabolically active. Several physical and molecular changes take place during this stage that makes them interesting to explore. The characteristic proteins synthesized in the stationary phase are indispensable as they confer viability to the bacteria.

Why is the 2nd major phase of microbial growth curve called as exponential phase?

The log phase (sometimes called the logarithmic phase or the exponential phase) is a period characterized by cell doubling. If growth is not limited, doubling will continue at a constant rate so both the number of cells and the rate of population increase doubles with each consecutive time period.

What happens in the stationary phase of bacterial growth?

growth is followed by the stationary phase, in which the size of a population of bacteria remains constant, even though some cells continue to divide and others begin to die. During the stationary phase, the rate of bacterial cell growth is equal to the rate of bacterial cell death.

What is exponential growth phase?

The exponential phase of growth is a pattern of balanced growth wherein all the cells are dividing regularly by binary fission, and are growing by geometric progression. The cells divide at a constant rate depending upon the composition of the growth medium and the conditions of incubation.

Why is bacterial growth called exponential?

Bacterial growth is proliferation of bacterium into two daughter cells, in a process called binary fission. Hence, bacterial growth occurs. Both daughter cells from the division do not necessarily survive. However, if the number surviving exceeds unity on average, the bacterial population undergoes exponential growth.

What are the phases of growth of bacteria and what does each represent?

The bacterial growth curve represents the number of live cells in a bacterial population over a period of time. There are four distinct phases of the growth curve: lag, exponential (log), stationary, and death. The initial phase is the lag phase where bacteria are metabolically active but not dividing.

What is the third phase of bacterial cell growth?

The third phase of bacterial cell growth is called the “stationary phase”. As you can probably guess, this phase involves a slow-down in the growth of the cells and the colony.

What is the log phase of the bacterial growth curve?

The bacterial growth curve represents the number of live cells in a bacterial population over a period of time. Lag Phase: This initial phase is characterized by cellular activity but not growth. Exponential (Log) Phase: After the lag phase, bacterial cells enter the exponential or log phase.

How long does the lag phase of bacteria last?

The lag phase can go on for several hours, or many days, depending on the particular bacteria, and the conditions it is living in. The second phase of bacterial growth is called the “log phase”.

What happens during the death phase of bacteria?

The death phase is characterized by an exponential decrease in the number of living cells. Bacteria require certain conditions for growth, and these conditions are not the same for all bacteria.