No, plant and animal cells do not lack nuclei. In fact, the nucleus is a defining characteristic of eukaryotic cells, which includes both plant and animal cells.

Here's why:

* The nucleus contains the cell's genetic material (DNA). This DNA is essential for the cell's function, growth, and reproduction.

* The nucleus controls the cell's activities. It directs the synthesis of proteins and other essential molecules.

While plant and animal cells have nuclei, they do have some key differences:

* Plant cells have a cell wall in addition to a cell membrane. This provides structural support and protection.

* Plant cells have chloroplasts, which are responsible for photosynthesis. Animal cells do not have chloroplasts.

* Plant cells often have a large central vacuole, which stores water and nutrients. Animal cells may have smaller vacuoles.

So, to summarize: both plant and animal cells have nuclei, and they are crucial for the cells' function.