An introduction to cell theory. Uses examples of abiogenesis as a contrast to modern cell theory.

1. “All living things …”
• grow
• use energy
• are made of cells
• can die
• require nutrients
• exchange gases with their
environment
• move
• depend on other living things
• reproduce!
• need water

2. “All living things …”
• grow
• use energy
• are made of cells
• can die
• require nutrients
• exchange gases with their
environment
• move
• depend on other living things
• reproduce!
• need water

3. Where do living
things come from?
What are they made
of?
cc licensed flickr photo by Brian Hillegas: http://flickr.com/photos/seatbelt67/502255276/

4. Tadpoles

5. Tadpoles
come from mud

6. Maggots
cc licensed flickr photo by Clintus McGintus: http://
flickr.com/photos/clintus/2523629054/
came from
rotting meat
cc licensed flickr photo by simplerich: http://flickr.com/photos/simplerich/
1393197323/

7. Spontaneous generation (abiogenesis):
a theory which explains that living
organisms can be spontaneously
created from non-living matter
Not an unreasonable explanation for
societies which didn’t have the right
technology to look at what living things
are made of.

8. The right technology
•Invented in Holland in 1590
•First cell seen/drawn by
Robert Hooke in mid 1600s.

9. Looked at cork bark (made of dead cells).
The small, empty spaces that he saw
reminded him of a small room. He called
them “cells”.

10. The first living cells were seen
by Antonie van Leeuwenhoek.

11. The discovery of cells led to the end of spontaneous
generation as a viable theory.