Cells are the basic function and structure of all living things. Everything is made of cells, including you and me!

Three scientists discovered cells and created the cell theory. The three parts of the cell theory are that all living things are made of cells, all cells come from other cells, and that cells are the basic structure of all living things.

Scientist #1: Anton Van Leeuwenhoek

After the invention of the microscope, Anton Van Leeuwenhoek created his own simple version of the compound microscope. With it, he observed the scrapings of teeth, and named the bacteria he had found animalcules.

Scientist #2: Robert Hooke

While looking at a piece of cork underneath his microscope, Robert Hooke observed little chambers. These chambers reminded him of cells, or the rooms that monks stayed in at monasteries. So, he named the chambers cells.

Scientist #3: Matthias Schleiden

After years of studying plants under his microscope, Matthias Schleiden realized something that all plants had in common: all plants are composed of cells. A way to remember this is to say "Schleiden (sliding) down a grassy hill."

Scientist #4: Theodor Schwann

After studying animal cells, Theodor Schwann, a zoologist, came to the conclusion that all animals are made of cells. A way to remember this is to think that Schwann sounds like swan, which is an animal.

Scientist #5: Rudolf Virchow

Rudolph Virchow researched cells and found that all come from preexisting cells. One way to remember this is that Virchow rhymes with cow, and all cows have to come from another cow.