1. Chapter 3 Cells
3.1 Cell Theory

2. KEY CONCEPT Cells are the Basic unit of life.

3. Discovery of Cells
The cell theory grew out of the work of many scientists and improvements in the microscope.
A cell is the smallest unit capable of carrying out life functions
More was learned about cells as microscopes improved.
The cell theory is a concept of biology.

4. Examples of Cells Amoeba Proteus Plant Stem Bacteria Red Blood Cell
Nerve Cell

5. Wacky theory of cell history
Cell Theory

6. Discovery of Cells Zacharias Jannsen
Man who invented the compound microscope

7. Discovery of Cells Robert Hooke
In 1665 he used a microscope to look at a thin slice of cork
Responsible for naming cells after looking at cork
Named them after the chambers that monks lived in

8. Discovery of Cells Anton van Leeuwenhoek
In 1674, first scientist to observe and describe living cells from looking at pond water
Called them
Animalcules

9. The Cell Theory Matthias Schleiden German Scientist
1838, concluded all plants are made of cells
Cofounded the Cell Theory

10. The Cell Theory Theodore Schwann German Zoologist
1839, concluded all animals were made of cells
Cofounder of cell theory

11. The Cell Theory Rudolph Virchow German Scientist
1855, concluded all cells come from other cells
Cell Division

12. Cell Theory 3 major principles of the Cell Theory
All organisms are made of cells
All existing cells are produced from other living cells
The cell is the most basic unit of life

13. There are two types of cells: Prokaryote and Eukaryote
All cells share certain characteristics.
Cells tend to be microscopic.
All cells are enclosed by a membrane which regulates the flow of materials into and out of the cell.
All cells are filled with cytoplasm – a jelly like
substance containing dissolved molecules
like proteins and minerals.
cell membrane
Bacterium
(colored SEM; magnification 8800x)
cytoplasm

14. There are two types of Cells: Prokaryotes and Eukaryotes
Do not have a nucleus.
DNA in cytoplasm
Do not have membrane-bound organelles
Single celled organisms
Less complex
Ex Bacteria
cell membrane
cytoplasm

15. There are two types of Cells: Prokaryotes and Eukaryotes
Have a nucleus.
DNA in nucleus
Eukaryotic cells have membrane-bound organelles.
Single or Multicellular
More complex and
Specialized
Ex. Most plant and
animal cells
nucleus
organelles
cell membrane