1. The Cell Theory

2. The Players
There are several scientists that contributed to the establishment of the cell theory
Collaboration
Two or more people work together for a common goal

3. The Players Hans & Zacharias Jenssen Robert Hooke
Antony van Leeuwenhoek
Matthias Schleiden
Theodor Schwann
Mohl & Schultze
Rudolf Virchow

4. Contributions
1. Hans (father) & Zacharias (son) Jenssen created the first compound microscope
Able to magnify objects about 7x their actual size
1595

5. Contributions
2. Robert Hooke was known for his observations and publications dealing with both microscopy and astronomy
In 1665 Hooke made observation of a thin slice of cork (tree bark) & drew them
Saw small compartments that he called cellulae (latin for “cells”)
Looked like the rooms (cells) of a monastery

6. Can You See What Hooke Saw?6

7. Contributions
3. Antony van Leeuwenhoek made over 500 simple (as opposed to compound) microscopes around 1670
Excellent lens grinder
Simple scopes could magnify 200x
Observed anything that he could find
First to see living cells under microscope

8. POND WATER…….SAW Micro-organisms……Single Celled.8

9. Contributions
4. Matthias Schleiden was a botanist that came to a very important conclusion in 1838:
Observed plant tissues from multiple species
Realized that all plants are made of cells

10. Plant Cell

11. Contributions
5. Theodore Schwann was a zoologist and a good friend of Schleiden
Heard about Schleiden’s findings
Schwann had observed that all the animals he observed were made of cells in 1839

12. Animal Cell

13. Schleiden and Plants
When you weed your garden, you are uprooting plants from the soil.
Schleiden was the first scientists to say that those plants are made up of cells. 13

14. Schleiden is Weedin’ 14

15. Schwann and Animals
Schwann was the first scientists to say that all animals are composed of at least one cell. 15

16. Together…
All living things
are composed
of cells! 16

17. Contributions 6. Mohl & Schultz 1839
Developed the idea that cells are the basic unit of living things
Nothing that is alive is simpler than a cell

18. Contributions 7. Rudolf Virchow studied and taught medicine
Noticed all cells always came from preexisting cells (1855)

19. Cell Theory The Cell Theory
By the end of the 19th century, all of these ideas and concepts were widely accepted.
Collectively, they became known as:
The Cell Theory 19

20. Summary of the Cell Theory (19th Century)
1. All living things are made of one or more cells.
Plants and animals are composed of cells and of products made by cells.
2. Cells are the basic units of structure and function in organisms.
Living things carry on their activities because of the activity of their component cells.
3. All cells arise from pre-existing living cells. 20

21. Summary of the Cell Theory (Added in the 21st Century)
1. All cells are made basically the same way
They all have the same basic organelles in basically the same place within the cell. Even cells from other organisms are basically the same as your cells
2. Energy flows within cells
The final break down of food occurs within your cells. Cells are able to harvest energy from food and use energy to drive activities.
3. Cells contain hereditary information (DNA) that must be passed to new cells when they divide.
Every cell has DNA as its molecule of heredity, and it passes DNA on to every new cell that is formed. 21