The Growth Curve of Cells

The bacteria will grow if they are given some nutrition. This graph shows the growth

curve of bacteria cells. The line on the graph illustrates the relationship between Time

(hours) of Cells for growing until death and the total of viable cells/ml. There are no cells

in the initial time because the bacteria need a time to adapt with the surrounding. This

condition is known as log phase which nutrition is not eaten by the bacteria. Suddenly,

the viable cells increase of 1 cells/ml. It means that the bacteria start to consume the

nutrition and pass the adaptation time. In 9 hours, it remains constant at 1 cells/ml. It is

called a lag phase. It is the phase that the quantity of nutrition is more than the bacteria.

One hour later, we see a small increase of 2 viable cells/ml. This upward trend continues

in 18 hours, the viable cells go up substantially to 6 cells/ml. In biotech, this phase is

named as exponential phase. There are more bacteria start to grow and consume the

nutrition. In 22 hours, it reaches a peak of 9 cells/ml. The exponential phase, the increase

of cells, is change to stationery phase. In this phase, the viable cells also remain constant

at 6 cells/ml and it is stand until 31 hours. It because of the bacteria equal the nutrition. In

36 hours, the viable cells fall by 3 cells/ml. It represents a decrease to the level of 18

hours. It is no wonder because the bacteria compete each other to get their nutrition.

Consequently, some of them are death. In 42 hours, the cells drop to 1 cells/ml. The

nutrition is less than the bacteria. It is called as death phase. By studying this graph, we

can predict this downward trend to continue in the next hours.