Question

Two to three days after seeding cells in new media, you will notice that the pH of cell culture medium, as monitored by phenol red, will change over time unless it is replaced. What causes the media to change color assuming there is no microbial contaminations, that the cells are still healthy and kept in a functioning CO2 incubator such as the ones we have in the lab?

Answer 1

Answer: The change of pH is based on the by-product of the cell medium

Explanation:

The phenol red indicator changes color based on the by-product of the seeding cells. If acid, it will turn yellow (carbohydrate consumption). If basic, it will turn red (peptone consumption).