Here's why:

* Nucleus: The nucleus is the control center of a cell. It contains the cell's genetic material (DNA) and directs all cellular activities.

* Plant cells: Plant cells, including those in a watermelon, are eukaryotic cells. This means they have a membrane-bound nucleus that houses their DNA.

So, the next time you enjoy a slice of watermelon, remember that each juicy cell contains a tiny, bustling nucleus!