1. The Basic Unit of Life
2A part 2

2. Objectives:
I will be able to explain the three parts of the cell theory.
I will be able to describe the four basic functions that all cells perform

3. cytology: the study of cells
Robert Hooke
Anton van Leeuvenhoek
Matthias Schleiden
Theodor Schwann
Rudolf Virchow

4. Robert Hooke
Cytology can be traced back over 300 years to the English scientist Robert Hooke.

5. Robert Hooke
In 1665 he published Micrographia - a report of his use of simple compound microscopes capable of magnifying approximately
30 times to
observe cork.

6. Robert Hooke
The neat rows of little boxes reminded him of rows in a prison or a monastery - he therefore named the "cells." (“coined”)

7. Robert Hooke In 1665 Robert Hooke was the first to use the term cell.
He saw only the dead, empty walls of cork cells.

8. Anton van Leeuwenhoek
Around the same time as Robert Hooke, Anton van Leeuwenhoek also began to observe tiny objects with microscopes.

9. Anton van Leeuwenhoek
He looked at drops of lake water, scrapings from teeth and gums, and water from rain gutters.

10. Anton van Leeuwenhoek
He saw tiny moving organisms which he called “animalcules,” meaning “little animals.”

11. "All plants are composed of cells."
Matthias Schleiden
A German botanist
In 1838 said,
"All plants are composed of cells."

12. "All animals are composed of cells."
Theodor Schwann
A German zoologist
In 1839 said,
"All animals are composed of cells."

13. A German doctor who is referred to as the "Father of Pathology,"
Rudolf Virchow
A German doctor who is referred to as the "Father of Pathology,"
In 1855 he proposed that new cells are formed only from cells that already exist.

14. The three basic principles of the cell theory
All cells come from preexisting cells.
All living things are made of cells and the products of cells.
Cells perform the functions of living things.

15. Cellular functions Use energy Manufacture materials
Respond to environment
Reproduce