1.  All organisms are composed of cells  Cells are the smallest living unit of living things  All cells come from cells The Cell Theory Spontaneous generation

2.  Cell theory  Germ theory of disease  Theory of evolution  Atomic theory  Heliocentric theory of the solar system  Universal gravitation  Theory of relativity  Quantum theory  String theory Important Scientific Theories

3. ProkaryotesEukaryotes What kinds of organisms are they? What are the characteristics of their cells?

4. The Prokaryotic Cell Cell membrane (plasma membrane) Boundary Semi-permeable

5. The Prokaryotic Cell Ribosomes Not membrane-bounded Protein synthesis

6. The Prokaryotic Cell Cell wall Rigid Permeable

7. Nucleoid Genetic material (DNA) The Prokaryotic Cell

8. Flagella Protein filaments Motility The Prokaryotic Cell

9. The Eukaryotic Cell Ribosomes Bound to ER (rER) – secreted proteins Free – cytosol proteins

10. The Eukaryotic Cell Nucleus Genetic material (DNA) Chromatin (chromosomes) Nuclear envelope (with pores) Nucleolus

11. The Eukaryotic Cell Mitochondria Energy transduction Aerobic respiration → ATP 2 membranes Own DNA (16,000 bp) & ribosomes Reproduce independently by division outer membrane inner membrane inter-membrane space matrix

12. The Eukaryotic Cell Chloroplasts Energy transformation: photosynthesis Photosynthetic eukaryotes only 3 membranes Own DNA & ribosomes Reproduce independently by division

13. The Eukaryotic Cell Endoplasmic reticulum rough: synthesis of secreted proteins smooth: lipid synthesis sER rER vesicle

14. The Eukaryotic Cell Golgi apparatus Modification of secreted proteins Distribution of secreted proteins Vesicle Transport of secreted proteins

15. The Eukaryotic Cell Lysosomes Small membrane sacs “Recycling center” Enzymes break down molecules

16. The Eukaryotic Cell Vacuole Storage Phagocytosis Water balance etc.

17. The Eukaryotic Cell Cytoplasm Everything outside the nucleus Includes organelles Cytosol Gel-like fluid of cytoplasm Does not include organelles Proteins, amino acids, nucleotides, salts, small molecules… Cytoskeleton Networks of protein fibers Structure, motility, organization, transport…

18.  Similar in size to prokaryotic cells  Two membranes  Own DNA  Own ribosomes, prokaryote-like  Divide independently  DNA sequence like prokaryotic genes The Endosymbiosis Theory ancestral cell membrane infolding creates nucleus, ER endosymbiosis results in mitochondria ancestral animal cell ancestral plant cell endosymbiosis results in chloroplasts

19. Why are prokaryotes small and eukaryotes large?