1. + A Tour of the Cell

2. + Main Point #1 Eukaryotic cells contain organelles with their own membranes Allows each organelle to be highly specialized and efficient “Eukaryotic cells maintain internal membranes that partition the cell into specialized regions”

3. + The Prokaryotic Cell (Bacteria) Completely open DNA “floats” in the nucleoid region Contains ribosomes but no organelles Cell contained in a cell wall

4. © Dennis Kunkel Microscopy, IncDennis Kunkel Microscopy, Inc

5. + Prokaryotes  Eukaryotes Not really sure how it happened Flexibility in cell shape and size? Somehow, eukaryotes ended up with internal membranes Endosymbiosis?

6. + Prokaryotic Cell vs. Eukaryotic Cell

7. + Our Cells - Eukaryotes DNA encased in membrane-bound nucleus Compartmentalized organelles Approx 10 times as large as bacterial cells

8. + Main Point #2 The nucleus stores DNA which codes for proteins that are made in ribosomes

9. The Nucleus Contains most of the genes Generally the largest organelle Protected by the nuclear envelope (double membrane)

10. The Nuclear Envelope –A Double Membrane Nuclear pores control what gets in and out 2 layers of membrane – the nucleus is important! Protects our DNA

11. This image is copyright Dennis Kunkel at www.DennisKunkel.comwww.DennisKunkel.com Nuclear Pores Ribosomes Nucleus with Nuclear Pores (TEM x 73,200) DNA

12. Nucleolus (plural – nucleoli) Spherical structure(s) found within nucleus Make ribosomes Not related to DNA

13. Nuclear Control of Protein Synthesis DNA in nucleus RNA leaves nucleus Ribosome translated into protein in cytosol

14. Ribosomes Protein factories Ribosomes are found in all domains of life But each domain’s ribosomes are slightly different (ours are larger) A cell has millions of ribosomes

15. Free Ribosomes Float in the fluid of the cell called the cytosol Makes all proteins that are needed within the cell

16. Bound Ribosomes Ribosomes temporarily attached to the Endoplasmic Reticulum Makes all proteins that will be shipped elsewhere

17. + Main Point #3 Each membrane bound organelle contains a unique environment Contain specific enzymes, proteins etc. to play a specific role

18. The Endoplasmic Reticulum A bunch of membranes connected to the nuclear envelope Makes more membrane 2 distinct parts Smooth Rough

19. Smooth ER – No ribosomes Synthesizes lipids (such as membranes), hormones Important in breaking down macromolecules Detoxifies drugs and poisons Endomembrane

20. Rough ER – Studded with Ribosomes Packages proteins made in the ribosomes into vesicles I.e. some white blood cells make antibodies- proteins that fight viruses- to be shipped to the blood

21. + Rough Endoplasmic Reticulum with Ribosomes (TEM x61,560) This image is copyright Dennis Kunkel at www.DennisKunkel.com www.DennisKunkel.com

22. The Golgi Apparatus Center of manufacturing, warehousing, sorting and shipping ER  Vesicle  Golgi  Final destination

23. + Golgi Apparatus, (TEM x145,700) This image is copyright Dennis Kunkel at www.DennisKunkel.com www.DennisKunkel.com Golgi Apparatus Vesicles

24. Lysosomes Made by ER and Golgi Membrane-bound sac of digestive enzymes Hydrolyzes all major forms of macromolecules

25. + Lysosomal Storage Diseases Pompe's disease – lysosomes lack the enzyme to break down glycogen, liver is damaged Tay-Sachs – lysosomes can't break down lipids, lipids accumulate in brain http://www.unitedpompe.com/aboutpompe.cfm

26. + Mitochondria and Chloroplasts Both are Membrane-bound organelles Contain double membranes Contain their own DNA and ribosomes Operate somewhat independently Theorized to have come from eukaryotes incorporating bacteria into the cell http://www.ruf.rice.edu/~bioslabs/studies/mitochondria/mitorigin.html

28. + Evidence for Endosymbiotic Theory Chloroplasts and mitochondria have 2 membranes Chloroplasts and mitochondria have their own DNA and ribosomes Chloroplastic and mitochondrial ribosomes are similar to bacterial ribosomes Similar size to bacterial cells

29. Mitochondria Specialized membranes and enzymes for cellular respiration Krebs + Ox Phos

30. + Mitochondria, (TEM x190,920) This image is copyright Dennis Kunkel at www.DennisKunkel.com www.DennisKunkel.com

31. NucleusNucleolus Mitochondria Endoplasmic Reticulum Ribosomes Liver cell nucleus and nucleolus (TEM x20,740). This image is copyright Dennis Kunkel at www.DennisKunkel.com www.DennisKunkel.com

32. Chloroplasts (only in plants, algae) Specialized thylakoids for light reactions Specialized stroma with enzymes for Calvin cycle

33. + Chloroplast, (TEM) Image copyrighted by University of Central Arkansas Thylakoids

34. http://www.studiodaily.com/main/searchlist/6850.html