1. Cells and Cell Theory

2. Leeuwenhoek • 1673-1723 Anton van Leeuwenhoek
Saw “wee beesties” and “animalcules”
He is known as the “Father of Microscopy
described live microorganisms
observed in teeth scrapings, rain water,and peppercorn infusions.

3. The First Observations –Robert Hooke
1665
Used a compound microscope (2 lenses)
Looked at cork under microscope composed of little boxes or cells
Named what he saw, “cells” .

4. Schleiden & Schwann Development of the CELLTHEORY
• Matthias Schleiden (1838) German Botanist – using a microscope proposed that all plants are composed of cells
• Theodor Schwann (1839) German Zoologist – using a microscope proposed that all animals are composed of cells
• Together they stated:
– Cells are the elementary particle of all living organisms
– All cells are alive – independent to the organisms to which they belong

5. Virchow German pathologist He is known as the “Father of Pathology
• 1858, Rudolf Virchow
said cells arise from preexisting cells.
German pathologist
He is known as the
“Father of Pathology

6. Cell Theory Cell Theory * • All living things are composed of one or
more cells
• Cells are the basic units of structure
and function in an organism
• Cells come only from the reproduction
of preexisting cells
* Named for the Monk prayer cells

7. Cells Eukaryotic versus Prokaryotic Cells
• Prokaryotic - Cells lacking a nucleus.
• Eukrayotic - Cells containing a nucleus.
– Organelles - Membrane-bound bodies found within eukaryotic cells.

8. Types of Cells Two Basic Types of Cells • Prokaryotes:
– prounounced: pro-carry-oats
• Eukaryotes
– Proun: you-carry-oats

9. Prokaryotes Smaller No true nucleus – loose genetic material
Includes Archaea & Bacteria

10. Eukaryotes Eukaryotes
• Larger more complex cells that make up most familiar life forms:
plants, animals, fungi, algae
• Surrounded by a cell
membrane made of
lipids