1. Cells

2. Cell Scientists Robert Hooke looked at cork under a microscope 1 st to use term “cell”

3. Cell Scientists Anton van Leeuwenhoek looked at pond water 1 st to see living cells

4. Cell Scientists Schleiden, Schwann, & Virchow came up with the cell theory

5. The Cell Theory

6. Parts of the Cell Theory All living things are made of one or more cells Cells are the basic unit of structure & function in organisms Cells come only from the reproduction of pre- existing cells

7. Prokaryotic vs Eukaryotic Cells

8. Prokaryotic Cells Appeared 3.5 billion years ago Primitive, simple Small in size No membrane-bound organelles Smaller ribosomes Single, circular chromosome BACTERIA

9. Eukaryotic Cells Appeared 1.5 billion years ago Complex Contain membrane- bound organelles Larger ribosomes Paired, linear chromosomes NUCLEUS

10. Parts of a Eukaryotic Cell

11. Plasma Membrane Also called the Cell Membrane Separates cell from its environment

12. Plasma Membrane Semi- permeable Allows only certain molecules to enter or exit

13. Plasma Membrane Phospholipid Bilayer Embedded with proteins Fluid-mosaic Model

14. Nucleus “Boss” or “Brain” of the cell Controls cellular activities Contains DNA (chromosomes)

15. Nucleus Nuclear Membrane Surrounds nucleus Double membrane Contains nuclear pores (holes)

16. Nucleus Nucleolus Produces ribosomes Ribosomes leave through nuclear pores

17. Cytoplasm Cytosol Fluid portion Organelles Membrane-bound compartments that carry out specific functions

18. Mitochondria Breaks down glucose to CREATE ENERGY (ATP) Active cells (muscle) -> hundreds of mitochondria Inactive cells (fat) -> few mitochondria Have own DNA Have a double membrane

19. Ribosomes Create proteins Composed of 2 interlocking subunits Some float free in cytosol Some attach to the ER

20. Endoplasmic Reticulum (ER) Intracellular highway 2 Types Rough ER Smooth ER

21. Endoplasmic Reticulum (ER) Rough ER Covered in ribosomes Produces phospholipids and proteins

22. Endoplasmic Reticulum (ER) Smooth ER Lacks ribosomes Produces lipids, estrogen, & testosterone Helps detoxify drugs & poisons Increased use = increased smooth ER Possibly linked to increased tolerance

23. Endoplasmic Reticulum (ER)

24. Transport (FedEx of the cell) Receive vesicles from ER Can modify packages en route Golgi Apparatus

25. Lysosomes Contain digestive enzymes Digest organic molecules, worn organelles, or dying cells Vesicles

26. Cilia Hair-like Short & numerous Flagella Tail-like Long & less numerous Cilia/Flagella

27. Plant Cell versus Animal Cell Plant Cell versus Animal Cell

28. Cytoskeleton Network of microtubules & filaments Gives the cell shape Holds organelles in place Animal Cells Only!

29. Centrioles Used during cell division Animal Cells Only!

30. Cell Wall Rigid layer surrounding plasma membrane Made of cellulose Pores allow water, ions, & other molecules to pass Bacteria, some protists & fungi also have cell walls Plant Cells Only!

31. Chloroplast Contain chlorophyll Site of photosynthesis Energy (sunlight) -> food Contain own DNA Have a double membrane Plant Cells Only!

32. Central vacuole Large, fluid-filled organelle Stores water, ions, enzymes & waste Can be up to 90% of cell’s volume Animals cells have small vacuoles Why so big in plants? Plant Cells Only!