2. All Living Organisms are Composed of One or More Cells The Cell is the Basic Unit of All Living Things All Cells Come From Pre-existing Cells

3. All Cells Contain a Membrane, Cytoplasm… … and the Same Basic Organic Compounds Proteins Lipids Nucleic acids Carbohydrates Elements Carbon Hydrogen Oxygen Nitrogen Phosphorous Sulfur

4. Consist of Protein & Nucleic Acid (DNA) Technically, Not a Living Thing No Membrane & Cytoplasm Viruses Do Not… Reproduce Convert Energy Consist of Cells

5. Simplest Cells Does not Have a Nucleus DNA Floats in Cytoplasm Contains Ribosomes Very Small > 5  m No membrane Bound Organelles Only form Unicellular Organisms

6. Includes All Forms of Bacteria

7. Complex Cells Contains Organelles Has a Nucleus Forms Both Unicellular & Multicellular Organisms Relatively Large (> 5  m) Nucleus Holds Cell’s DNA Come in Various Shapes & Sizes Includes All Protists, Fungi, Plants & Animals

9. Eukaryotic CellsProkaryotic CellsViruses  Membrane  Nucleus  Organelles  Large & Complex  Plants, Animals, Fungi, Protists  > 5  m  Visible under low power  Membrane  No Nucleus  DNA free in cytoplasm  Ribosomes only structures  Small & Simple  Bacteria  1 – 5  m  Visible under high power only  No membrane  Nucleic Acid (DNA) & Protein  Cannot reproduce on own  Cannot carry out metabolism on own  < 1  m  Not visible with our microscopes

10. 1.0  m 15.0  m