It's the gel-like substance that fills the cell and is where many of the cell's important processes happen, like:

* Metabolic reactions: The cytoplasm is the site of many chemical reactions that keep the cell alive.

* Organelle movement: Organelles within the cell move around within the cytoplasm.

* Cell shape: The cytoplasm helps to maintain the cell's shape.

So, whether it's a plant cell with a rigid cell wall or an animal cell without one, they both have cytoplasm.