Yeast Cells?

Question

Hypothetical situation: In a period of 120 hours, a yeast cell population grows. At the beginning there are 30 cells. It peaks at 72 hours where there are 330 cells. At 96 hours, there are 180 cells. Finally, at 120 hours, there are 90 cells.

Why did the yeast cells peak then decline in number?

Answer 1

The cells reached their capacity and start dying off.

Answer 2

are used for fermentation of food items as it contains benefittable bacteria

Answer 3

While the yeast cell population was small, there was an excess of nutrients, causing the population to grow.  At 72 hours, when the population peaks, the amount of cells in the population exceed the carrying capacity, or the amount of organisms that can be supported in the environment, and this is because there is no longer enough food for the cells to all exist, there is too much waste in the environment, etc.  when this happens, the population size begins to drop as individuals die off.  That leads to the peak and decline that you're describing.

hope that helped!

Answer 4

Yeast produce alcohol as an end product of their fermentation of sugars.  High concentrations of alcohol is lethal to yeast causing them to die off.

Answer 5

They use up the nutrients.

Answer 6

The yeast population will grow exponentially as long as there are ideal growth conditions ie food, water correct temperature etc. When the population reaches its optimum the population is stable. However, the population declines when food or water supply is in short supply and build up of toxic metabolites in the culture.

Hope this helps!

Answer 7

The yeast cells breached their environment's carrying capactiy (the maximum number of a species an environment has the space, food, and resources for) and they started to die.