Answer:
The cell theory states that the basic, or smallest, unit of life is the cell and that all living organisms are composed of cells.
In the 19th century, 2 biologists named Theodor Schwann and Matthias Jakob Schleiden created the cell theory. Let me explain a little more about the cell theory
The cell theory simply states that all cells must reproduce to create new cells. The genetic material of a parent cell is passed to daughter cells.
Mitosis - While this may seem like a fancy word, mitosis is just the way that single-celled organisims reproduce. Parent cells simply split into two identical daughter cells.
sexual reproduction - is when an egg cell and a sperm cell unite (egg is female and sperm is male), creating a non-identical daughter cell. This new cell is half of the mother's genetic material half of the father's, and this is how we were created and why you probably look like your mom and like your dad.
Cell theory also believes that cells are similar in chemical makeup. For example, all cells, no matter where they are in the body, have carbon. All cells change food into energy, which is used to carry out the functions needed to have a healthy life.
Hope this helped you!