1. 2.1 The Structure & Functions of Eukaryotic Cells

2. Cells Smallest living unit Most are microscopic

3. Defining a Cell A cell is a confined system of potentially self perpetuating linked organic reactions that are catalyzed step-wise by enzymes.

4. Principles of The Cell Theory All living things are made of 1 or more cells Smallest living unit of structure and function of all organisms is the cell All cells arise from pre-existing cells (this principle discarded the idea of spontaneous generation)

5. Cell Size

6. Small Cells have a large Surface Area-to-Volume Ratio. Why?

7. Why are S.A./Vol. Ratios Important? Surface area represents the “access” available to and from a cell for supplies. Volume represents how much has to be supplied. The more “access” you have to supply each unit of volume, the more efficient the cell is.

8. Characteristics of Living Cells Very complex Very small Self-replicating Autonomous/semiautonomous Homeostatic

9. There are 2 Cell Types Prokaryotic Eukaryotic

10. Prokaryotic Cells First cell type on earth (chemosynthetic) All are single celled (ie Bacteria)

11. Prokaryotic Cells No membrane bound structures inside Nucleoid instead of nucleus (region of DNA concentration). Organelles not bound by membranes

12. Eukaryotic Cells Internal membrane bound organelles Cytoplasm (cytosol, organelles + molecule & ions ) for metabolism Cell Membrane (Phospholipid bilayer) Can be Single or Multi-celled Protozoan

14. Eukaryotic Animal Cell

15. Animal Cell Micrograph

16. Eukaryotic Plant Cell

17. Plant Cell Micrograph

18. Cytoplasm Viscous fluid containing organelles components of cytoplasm –Interconnected protein filaments & fibers –Fluid = cytosol –Organelles (not nucleus) – storage substances

19. Nucleus Control center of the cell Contains nucleoplasm Wrapped by a nuclear envelope which is a double membrane. Nuclear pore complexes form openings in nuclear envelope Contains –Chromosomes (DNA) –Nucleolus

20. Nucleus Micrograph

21. Chromosomes (DNA) Hereditary material Chromosomes - DNA + proteins –Short, thick strands –form for cell division Chromatin - DNA + proteins –long, thin strands –form for interphase DNA is transcribed & translated into protein to express hereditary traits

22. Nucleolus Non-membrane bound Contains RNA & proteins Most cells have 2 or more. Directs synthesis of RNA Forms ribosomes

23. End of Part 1!