The Cell Theory Some Random Cell Facts The average human being is composed of around 100 Trillion individual cells!!! It would take as many as 50 cells to cover the area of a dot on the letter “i” WOW!!! 1665 - Robert Hooke 1665- English Scientist, Robert Hooke, examined cork cells. He is responsible for naming the spaces in cork “cells” – which is Latin for little rooms. 1673 - Anton Van Leuwenhoek 1673 - Dutch scientist, Anton Van Leuwenhoek, used a handmade microscope to observe pond scum & discovered single-celled organisms. He called them “animalcules” 1838 – Matthias Schleiden 1838- German Botanist, Matthias Schleiden, looked at plants cells. He concluded that cells are present in all living things. 1839 – Theodore Schwann 1839- German scientist, Theodore Schwann, stated that all animal tissues are composed of cells. He & Schleiden are credited with the first two parts of the cell theory. (The cell is the basic unit of life for all living things. All organisms are composed of one or more cells.) 1858 – Rudolf Virchow 1858- Rudolf Virchow, German physician, observed that cells could not develop from anything but existing cells. So he wrote the third part of the cell theory. (All cells come from existing cells.) Important Thoughts Cells carry on similar functions such as extracting energy from food to sustain life. Organisms grow by “adding on more cells,” NOT increasing the size of their cells. Why the Cell Theory is important? The basic discovered truths about cells, listed in the Cell Theory, are the basis for things such as: Disease/Health/Medical Research and Cures(AIDS, Cancer, Vaccines, Cloning, Stem Cell Research, etc.) What things are composed of cells? Give example. What things are not composed of cells? Give example. What are the three parts of the cell theory? A 15 year old and a 5 year old are made of cells, how are their cells different?