1. CELLS
The Basic Unit of Life

2. Cells are living things.
Lamprey

3. Cells Make up Plants

4. Cells make up all living things.

5. The Cell IS THE BASIC UNIT OF ALL LIFE ON EARTH.
Every organism (living thing) is made up of one or more cells.
*the average adult human body
is built out of more than
100 trillion cells!!

6. Most cells are extremely small and you need a microscope to see them.
**However: A bird’s egg,
A turtle’s egg, and
a Frog’s egg
are each an example of a very
large, single cell.

7. Technology and Discovery of Cells:
Cells were not known to exist until about 340 years ago.
The existence of cells became known because of the advancement of technology.

8. Here is how the existence of cells was discovered:
1. Most cells are too small to be seen by the unaided eye.
2,The existence of cells could not be discovered until a scientific tool could be made to actually see cells.
3. The Advancement of technology allowed the microscope to be invented in the 1600’s.
4. Then, using microscope , scientists were able to discover the existence of cells.

9. Cell theory 2. Cells are the basic unit of structure & function
 1. all known living things are made up of cells.
2. Cells are the basic unit of structure & function
3. all cells come from other living cells

10. Robert Hooke (1665)
English Scientist, discovered cells while looking at a thin slice of cork.
Using a microscope, Hooke found tiny room-like structure in dead cork specimens.
He called the structures “ cells”, and we have used the word cell ever since.
** named the tiny spaces cell

11. Anton Van Leeuwenhoek 1670’s
Used a handmade microscope to observe pond scum & discovered single-celled organisms **** first to see bacteria
found living cells in tooth scrapings too!
Today we know that the living cells he found were bacteria cells.

12. Cell Theory: The Cell Theory was able to be developed because of technology.

13. Here’s How a. During the 1700’2 and 1800’s the advancement of technology improved the quality of microscopes. b. Better quality microscopes allowed scientists to see cells and the structures inside of cells much more clearly. c. Clear cell structure views allowed scientists to understand how cells are built and what processes the structures perform to keep cells alive.

14. Schleiden and Schwann 1850’s
Schleiden: German Botanist, concluded that all plant are made of cells.
Schwann: German physiologist, who was a close friend of Schleiden, stated that all animal are made of cells.

15. Rudolf Virchow,1858
German physician, discovered that all living cells come only from other living cells.

16. Cell theory
It is a group of three rules that relates cells to all Living Things
It is based on the research work by Schleiden, Schwann and Virchow

17. Rule # 1. All living things are made of cell
Know the three rules of the cell theory
Rule # 1. All living things are made of cell
Rule #2. The cell is the basic unit of structure and function in all living things.
Rule #3 living cells come only from other living things. ( Virchow)

18. Remember
Structure tells how organisms are put together – living things are “built” cell by cell.
Function tells what processes a cell performs to help the cell maintain its homeostasis and stay alive.

19. Germ Theory of Disease
Microscopic organisms cause diseases.
Pasteur