Question

a population of yeast grows in a test tube under ideal conditions until it runs out of space in the test tube . which kind of curve would accurately show the changes in this population

Answer 1

The plot of the yeast population has some features that represent the conditions of the yeast cells at different times. Initially, the population does not change (lag phase). During this time, the cells assimilate nutrients and increase in size. Although the population remains unchanged because of change in size, both cell mass and optical density show some increase.

Following is the main part,

After that, the cell number starts increasing, ?rst slowly and then very rapidly. The cells in the population differ initially in metabolic rate and only some multiply, and then almost all the yeast cells multiply. This is the exponential phase (also called logarithmic phase). Growth rate at the exponential phase follows ?rst-order reaction kinetics. Following this, the growth rate slows down and ?nally the population enters the stationary phase. At this stage, because of nutrient shortage and accumulation of waste products, a few cells die and a few cells multiply, keeping the living population stable.