1. CELLS!!!

2. Cell Scientists Robert Hooke Anton van Leeuwenhoek
Looked at cork under a microscope
1st to use the term “cell”
Anton van Leeuwenhoek
Looked at pond water
1st to see living cells
Schleiden, Schwann, and Virchow
Came up with cell theory

3. Cell Theory All living things are composed of one or more cells
Cells are the basic unit of structure and function in all organisms
Cells come only from the reproduction of pre-existing cells

4. Prokaryotes Appeared 3.5 bya Primitive Small in size
No membrane-bound organelles
Smaller ribosomes
Single, circular DNA
Ex: bacteria

5. Eukaryotes Appeared 1.5 bya Complex Contain membrane-bound organelles
Larger ribosomes
Paired, linear chromosomes
NUCLEUS!

7. Parts of a Eukaryotic Cell

8. Plasma Membrane Also called the cell membrane
Separates cell from its environment

9. Plasma Membrane Semi-permeable
allows only certain molecules to enter or exit

10. Plasma Membrane Phospholipid bilayer Fluid-mosaic model
Embedded with proteins
Fluid-mosaic model

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

12. Nucleus Nuclear membrane Nucleolus Surrounds nucleus Double membrane
Contains nuclear pores (holes)
Nucleolus
Produces ribosomes
Ribosomes leave through nuclear pores

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

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

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

16. Endoplasmic Reticulum (ER)
Intracellular highway
2 types
Rough ER
Smooth ER

17. Rough ER
Covered in ribosomes
Produces phospholipids and proteins

18. Smooth ER Lacks ribosomes Produces lipids, estrogen, and testosterone
Helps detoxify drugs and poisons
Increased use = increased smooth ER
Possibly linked to increased tolerance

19. Endoplasmic Reticulum

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

21. Vesicles Lysosomes Contain digestive enzymes
Digest organic molecules, worn organelles or living cells

22. Vesicles Peroxisomes Neutralize free radicals (oxygen ions)
Detoxify alcohol and drugs
Breakdown fatty acids

23. Cilia/Flagella Cilia Flagella Hair-like Short and numerous Tail-like
Long and less numerous

24. Plant Cell Vs. Animal Cell

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

26. Animal Cells Only
Centrioles
Used during cell division

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

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

29. Plant Cells Only! Central vacuole Large, fluid-filled organelle
Stores water, ions, enzymes, and waste
Can be up to 90% of cell’s volume
Animal cells have small vacuoles