The major feature that plant cells have that animal cells do not is a cell wall.

Here's why this is significant:

* Structure and Support: The cell wall provides structural support and rigidity to the plant cell, allowing plants to grow upright and withstand external pressures.

* Protection: It acts as a protective barrier against invading pathogens and helps maintain the cell's shape.

* Regulation of Water: The cell wall plays a role in regulating water movement into and out of the cell.

While animal cells have a cell membrane, it's much thinner and less rigid than the cell wall. This allows animal cells to be more flexible and move around, which is necessary for their function.