1. The Cell

2. Definition of Cell note: only write down text in red A cell is the smallest unit that is capable of performing life functions.

3. Cell Theory All living things are made of cells. Cells are the smallest living units. All cells come from preexisting cells through cell division.

4. Who came up with this theory? 1.Robert Hooke(1665) First person to see cells, he was looking At cork and noted that he saw many boxes That look like prison cells Let’s call these things cells!

5. Who came up with this theory? 2. Schleiden (1838) All plants are made of cells! Onion skin cells

6. 3. Schwann - 1839 Who came up with this theory? All animals are made of cells! Human red blood cells

7. Who came up with this theory? 4. Virchow - 1855 All cells come from pre-existing cells!

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

9. How big are cells? Mostly Microscopic Measured in microns (µm) A µm is one millionth of a meter!

10. How big are cells? Bacteria (aka E.coli) Size=1 µm by 3 µm

11. How big are cells? Human red blood cell = 8 µm

12. How big are cells? Largest cell on the human body is the ovum 1000 µm in diameter (1 mm)

13. Two Types of Cells Prokaryotic Eukaryotic

14. Prokaryotic Do not have organelles surrounded by membranes Few internal structures Example: Bacteria

15. Eukaryotic Contain organelles surrounded by membranes Most living organisms are eukaryotes PlantAnimal

16. “Typical” Animal Cell

17. “Typical” Plant Cell