The genetic material, chromosomes, are stored in the nucleus of both plant and animal cells.

Here's a bit more detail:

* Nucleus: The nucleus is a membrane-bound organelle that acts as the control center of the cell. It contains the cell's genetic material in the form of DNA, organized into chromosomes.

* Chromosomes: Chromosomes are thread-like structures made up of DNA and proteins. They carry the genetic information that determines an organism's traits.

So, the nucleus is like a safe that protects and stores the cell's precious genetic information.