Yes, a nucleus is found in both plant and animal cells. It is a defining characteristic of eukaryotic cells.

Here's why:

* The nucleus is the control center of the cell. It contains the cell's genetic material (DNA) in the form of chromosomes. This DNA provides instructions for all the cell's activities, including growth, development, and reproduction.

* Both plant and animal cells are eukaryotic cells. This means they have a nucleus and other membrane-bound organelles.

* Prokaryotic cells, like bacteria, do not have a nucleus. Their DNA is located in a region called the nucleoid, which is not enclosed by a membrane.

So, whether it's a plant or animal cell, you'll find a nucleus as the central command center for all cellular operations.