1. M EET THE S CIENTISTS : D EVELOPING THE C ELL T HEORY

2. W HAT IS A CELL ?  The cell is the basic unit of structure and function in living organisms, including plants and animals.

3. A LL LIVING THINGS ARE MADE OF CELLS  Plants  Animals

4. T OOL USED TO VIEW CELLS  The microscope is used to magnify extremely small objects.

5. T IMELINE - 1590  Hans and Zacharias Janssen (1590)  Dutch lens grinders  Father and son  Produced first compound microscope (two lenses)

6. T IMELINE - 1665  Robert Hooke (1665)  English scientist  Looked at a thin slice of cork through a compound microscope and observed tiny, hollow room-like structures  He called them cells, but he only saw the outer cell walls because the cork cells were not alive.

7. T IMELINE - 1680  Anton van Leeuwenhook (1680)  Dutch amateur scientist  Looked at blood, rain water, and scrapings from teeth through a simple microscope.  He called the structures he saw “animalcules”.

8. T IMELINE - 1838  Matthias Schleiden (1838)  German botanist  Viewed plant structures under a microscope and discovered that they were made of cells

9. T IMELINE - 1839  Theodor Schwann (1839)  German zoologist  Viewed animal tissue taken from animal organs under a microscope and discovered the tissue was made of cells

10. T IMELINE - 1855  Rudolph Virchow (1855)  German physician  Stated that living cells come only from other living cells (This is a part of cell theory.)