Students Will:

1. Students Will: • Summarize the contributions scientists have made toward the cell theory. • State the cell theory.

2. Early Scientists’ Contributions

3. Robert Hooke • English scientist • Observed cork cells through a compound microscope he built in 1663 • Noticed the cork looked like many rectangular rooms, empty spaces he called “cells”

4. Anton von Leeuwenhoek • Dutch business man • Sold cloth but built microscopes in spare time • In 1674 he used a simple, one lens microscope to look at water droplets & scrapings from teeth/gums • Found many unicellular (one-celled) organisms moving about in these things & called them animalcules—”little animals”

5. Matthias Schlieden • German scientist • 1838 he concluded that All plants are made of cells based on his research & the research of others

6. Theodor Schwann • German scientist • 1839 he concluded that All animals are made of cells • Thus,he stated that ALL living things are made of cells

7. What they discovered wasn’t the end of the story • Schleiden & Schwann had made huge discoveries about the basic unit of life, but had failed to explain where cells came from originally. • Until this point they believed in spontaneous generation that Redi & Pasteur disproved

8. Rudolf Virchow • 1855, German scientist Virchow suggests that cells can only come from existing cells • “All cells come from cells,” he wrote

9. Schleiden, Schwann, Virchow, & et al developed the cell theory: the relationship b/w cells & living things. The cell theory states the following: 1. All living things are made of cells. 2. Cells are the basic unit of structure & function in living things. 3. All cells are produced from other cells.

10. Questions... • Who used the first microscope? • Who said that plants were made of cells? • Who coined the term “cell”? • Who said that all animals were made of cells? • Who said that cells must come from existing cells?