1. 1 B. Bruce - Cellular Life and its Origin Earliest life started 3.5 Billions Years Ago (BYA), Eukaryotes ~1.7 BYA

2. 2 B. Bruce - Cellular Life and its Origin Earliest photosynthetic life started 3.5 Billions

3. 3 Figure 1-9 Essential Cell Biology (© Garland Science 2010) B. Bruce - Cellular Life and its Origin All Life is contained in Cells

4. 4 Figure 2-20 Essential Cell Biology (© Garland Science 2010) ALL cells are surrounded by a membrane that is a bilayer of millions of individual lipids (this is not a macromolecule) B. Bruce - Cellular Life and its Origin

5. 5 All life can be be placed in one of three large “families” or groups

6. 6 B. Bruce - Cellular Life and its Origin All life can be be placed in one of three large “families” or groups Humans/ mammals

7. 7 Figure 1-11 Essential Cell Biology (© Garland Science 2010) Transmission Electron Micrograph of a single bacteria cell B. Bruce - Cellular Life and its Origin

8. 8 Figure 1-15 Essential Cell Biology (© Garland Science 2010) Eukaryote cells are much bigger than prokaryote cells and have many compartments B. Bruce - Cellular Life and its Origin

9. 9 Figure 1-15 Essential Cell Biology (© Garland Science 2010) Eukaryote cells have organelles including the nucleus that contains DNA in Chromosomes B. Bruce - Cellular Life and its Origin

10. 10 Figure 1-24 Essential Cell Biology (© Garland Science 2010) B. Bruce - Cellular Life and its Origin

11. 11 Figure 1-11 Essential Cell Biology (© Garland Science 2010) Despite differences in size and shape: prokaryote and eukaryote cells share features B. Bruce - Cellular Life and its Origin

12. 12 B. Bruce - Cellular Life and its Origin Nucleus Organelles Linear DNA Cells Cell membrane ribosomes nucleoid circular DNA Prokaryotes (bacteria) Eukaryotes (plants and animals and fungi) Structural differences between bacteria and eukaryotic cells