KEY CONCEPT Cells are the Basic unit of life.

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

2. The cell theory grew out of the work of many scientists and improvements in the microscope. • Many scientists contributed to the cell theory.

3. Anton van Leeuwenhook • In the 1600’s he was the first scientist to describe living cells using a simple microscope (contained one lens).

4. Robert Hooke • He was an English scientist who lived at the same time as van Leeuwenhoock. • Hooke was the first to identify cells and name them. • He observed that cork was composed of tiny, hollow boxes that he called “CELLS”.

5. Matthias Schleiden • German scientist who observed many types of plants and determined that all plants consist of cells.

6. Theodor Schwann • German scientist who determined that all animals consist of cells.

7. Rudolf Virchow • Proposed that all cells come from other cells.

8. The cell theory grew out of the work of many scientists and improvements in the microscope. • Many scientists contributed to the cell theory. • More was learned about cells as microscopes improved.

9. The cell theory grew out of the work of many scientists and improvements in the microscope. • Many scientists contributed to the cell theory. • More was learned about cells as microscopes improved. • The cell theory is a unifying concept of biology.

10. Before microscopes were invented, diseases were thought to be caused by curses and supernatural events.By using microscopes scientists realized they were entering a new world---one of microorganisms.Microscopes enabled scientists to view and study cells. • The History of the Cell Theory

11. Early studies led to the development of the cell theory. • The Cell theory has three principles. • All organisms are made of cells.

12. Early studies led to the development of the cell theory. • The Cell theory has three principles. • All organisms are made of cells. • All existing cells are produced by other living cells.

13. Early studies led to the development of the cell theory. • The Cell theory has 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.

14. All cells share certain characteristics.

15. Bacterium (colored SEM; magnification 8800x) All cells share certain characteristics. • Cells tend to be microscopic.

16. cell membrane Bacterium (colored SEM; magnification 8800x) All cells share certain characteristics. • Cells tend to be microscopic. • All cells are enclosed by a membrane.

17. cell membrane cytoplasm Bacterium (colored SEM; magnification 8800x) All cells share certain characteristics. • Cells tend to be microscopic. • All cells are enclosed by a membrane. • All cells are filled with cytoplasm.

18. There are two cell types: eukaryotic cells and prokaryotic cells.

19. nucleus cell membrane • There are two cell types: eukaryotic cells and prokaryotic cells. • Eukaryotic cells have a nucleus.

20. nucleus organelles cell membrane • There are two cell types: eukaryotic cells and prokaryotic cells. • Eukaryotic cells have a nucleus. • Eukaryotic cells have membrane- bound organelles. • (multi-cellular organisms) ex. -humans -other animals

21. nucleus organelles cell membrane • There are two cell types: eukaryotic cells and prokaryotic cells. • Prokaryotic cells do not have a nucleus.

22. nucleus organelles cell membrane cytoplasm • There are two cell types: eukaryotic cells and prokaryotic cells. • Prokaryotic cells do not have a nucleus. • Prokaryotic cells do not have membrane-bound organelles. • AKA (Unicellular organisms) ex. bacteria virus