Which technologies made it possible to maintain a controlled environment for cell cultures?

Cell counter inverted microscope and liquid nitrogen storage incubator are the technologies used in the cell culture.

Explanation:

Cell culture needs control environment for the production of cells in order to avoid contamination from other microbes. For this reason, liquid nitrogen storage incubator is used which decreases the temperature in order to slow down the process of cell division and other cellular processes and also provide safety from contamination. Cell counter inverted microscope is used to see the growth of the cells at the bottom of storage tank.