The Cell Theory – a timeline

1. The Cell Theory – a timeline • Late 1500’s: -first lenses used in Europe -used to determine cloth quality (weave and precision) -combos of lenses gave better view -Hans Janssen and son Zacharias invented first compound microscope in 1590

2. Robert Hooke ( 1665) • Used light microscope to look at thin slices of plant tissues -- cork • Looked empty, like monk’s chamber • Called tiny chambers “cells”

3. 1673 • Leeuwenhoek • first to view pond water organisms • First to see living microscopic orgs • Made careful sketches

4. Matthias Schleiden 1838 • German Botanist (plants) • All plants looked at were made of cells, so concluded: • “All plants are made of cells.”

5. Theodore Schwann -- 1839 • German scientist who studied animals -- zoologist • Saw that all animals he studied were cellular so concluded: • “All animals are made of cells.”

6. Rudolf Virchow -- 1855 • German physician who studied cell reproduction • “Where a cell exists, there must have been a preexisting cell…..”

7. The Cell Theory • All living things are composed of cells • Cells are the basic units of structure and function in living things • New cells are produced from existing cells