1. By the end of class, I will be able to…
Identify the three principles of the cell theory.
Describe how continuous investigations and/or new scientific information influenced the development of cell theory.
Identify the structure and function of cell organelles.

2. The Cell Theory

3. The Cell Theory History

4. The Cell Theory History
Robert Hooke
Discovers the cell (1665)
" little boxes or cells distinct from one another."

5. The Cell Theory History
Francisco Redi
makes first attempt at disproving “spontaneous generation” (1668)

6. The Cell Theory History
Anton van Leeuwenhoek
discovers “animalcules” (single-celled organisms) swimming in a drop of pond water (1674)

7. The Cell Theory History
Matthias Schleiden
proposes that plants are made of cells (1838)
Original drawing of plant cells by Schleiden.

8. The Cell Theory History
Theodor Schwann
Studied animal cells
After comparing observations with Schleiden, concludes that all living things are made of cells and that these cells form spontaneously by free-cell formation (1839)
Original drawings of plant and animal cells

9. The Cell Theory History
Rudolf Virchow
after studying cell division, reports that all cells come from pre-existing cells (1855)

10. The Cell Theory Establishes the following three principles:
All organisms are made of cells.
All existing cells are produced by other living cells.
The cell is the most basic unit of life.
Developed after a span of 200+ years of many scientists studying cells

11. Cell Theory Recap
After years of studying, the scientific community made the following conclusions...

12. All organisms are made of cells.

13. All existing cells are produced by other living cells.

14. The cell is the most basic unit of life.
Characteristics of Life
Cells
Homeostasis
Adapt (EVOLVE)
Respond to their Environment
Grow and Develop
Energy and Materials
Reproduce
DNA

15. Cell Structure
The development of technology, like the microscope not only allowed scientists to develop the cell theory, but also gave scientists a way to classify cells based on their structure.

16. Introduction to the Microscope