Result (part 2)

The Graph OD reading at the abs 600nm  versus time

This graph shows the curve of Saccharomyces Cerevisiae growth. Based on the graph , the lag phase starts from at 12.25  to 2.50 . But this phase does not last long because it is only for the adaptation of the  cells towards the  culture environment.At this time, the level of oxygen pressure is still high as well as temperature  and pH.

After  that ,  the growth increase from 2.5  to 6.5.The increment  at the log phase  (or also known as stationary phase) is due to cells’ growth rapidly and also the cells begin to uptake the glucose and minerals .The cell reproduction  has two types .Firstly , sexual  spore production and secondly , asexual budding .

After  the  log phase it supposes to be exponential phase . However ,  the  growth  goes  down  at 7.5 to 8.5 . However, there are two assumptions here:
1. It might because of the glucose level decreased too much  during the log phase due to the yeast consumption. 
2. Besides, this might also  because of the error during the sample is taken where the sample taken might have mixed with the previous sample and as a result, the glucose concentration changed during sampling.

At the peak of the graph,  the consumption of glucose is at maximum. Then the cells will stated to die off. When the concentration of glucose is going down therefore the  growth of cells decreased too due to more of cells death .

After  that, as more of the cells are death, the glucose level is increasing again and as the glucose increase, the cell’s growth is increasing too.

Then, after  the amount of cells are growing at the maximum rate, the amount of glucose becoming limited at 12.5 am.Therefore, more cells  tend to die and then, the toxin will start to produce from the cells. And this can cause the growth rate is going down abruptly.