The solar system is considered a natural system because it was made and controlled by natural forces, meaning, it was never influenced with human creations. It is considered as one of the products of the phenomenon of the physical world. Hope this answer helps you.
Here are the 3 parts of the cell theory:
1. Cells are the basic building blocks of any living things.
2. Any living thing is composed of more than 2 cells.
3. New cella arise from the old
