Final answer:
The cell theory states that all living things are made up of cells, which are the structural units of living organisms, and that living cells come from other living cells.
Step-by-step explanation:
The Cell Theory
According to the cell theory, all living things are made up of cells, which is the structural unit of living organisms, and living cells always come from other living cells. Each living thing begins life as a single cell. Some living things, such as bacteria, remain single-celled, while others, like plants and animals, grow and develop into many cells.