Why do plants have cell walls, and not animals? Think about how a plant grows. Plants grow tall, towards the Sun's light. In order to provide plants with the strength necessary to support their weight, the cells within the plant have this hard cell covering. If a tree were soft and mushy like an animal, do you think they could stand strong and tall?

What would happen if the cells in your body had cell walls? If an animal's body were made of plant cells, the animal would be very stiff, and unable to move easily. Instead of cell walls, animals use other creative solutions to give them strength. For example, many animal's bodies are built on a structure of bones. These bones allow the animal to have the strength to stand up, but the flexibility to move quickly.