1. Bio 178 Lecture 7 Cell Structure Copyright: J. Elson-Riggins

2. Reading Chapter 5 (& P 550) Quiz Material Questions on P 104 Chapter 5 Quiz on Text Website (www.mhhe.com/raven7)

3. Outline Microscopy (Cntd.) Prokaryotes Eukaryotes

4. Characteristics of Principle Cell Types 2 structurally different types of cells: PROKARYOTEEUKARYOTE True Nucleus?NoYes Membrane bound organelles? NoYes Kingdoms Bacteria Archaebacteria Protista Fungi Plantae Animalia

6. SEM - Dinoflagellate, Gonyaulax polyedra http://www.mcb.harvard.edu/hastings/dino.html

7. Immunofluorescence Microscopy Green = Anti-tubulin Red = Anti- vimentin http://www.img.cas.cz/dbc/gallery.htm

8. Prokaryotic Cells (Bacteria)

9. Prokaryotes Characteristics Simple Organization 1.Little compartmentalization. 2.Nucleoid region with a simple circle of DNA. 3.Ribosomes. Size ~ 1 to 10 µm.

10. Prokaryote Characteristics (Cntd.) Support Most prokaryotes have a strong cell wall (instead of internal support structures). Cell Shape Variable - rod (bacillus), sphere (coccus), comma (vibrio), spiral (spirillum).

11. Staphylococcus epidermidis Dr. Dennis Kunkel / Visuals Unlimited, http://www.visualsunlimited.com/browse/vu285/vu285886.html

12. Spirillum http://web.grcc.cc.mi.us/biosci/pictdata/103contents.htm

13. Bacillus

14. http://bioaulas.tioale.pro.br/aula_bacterias.php Vibrio Vibrio cholerae

15. Prokaryote Cell Walls Bacteria have cell walls of peptidoglycan (protein- carbohydrate), but Archaebacteria use other materials. Gram Staining Gram Positive: A thick wall with many layers of peptidoglycan that blocks the escape of the gram stain  Purple. Gram Negative: Only a thin peptidoglycan layer that allows the escape of the gram stain  Red.

16. Prokaryote Cell Walls

17. Importance of Prokaryotes Decomposition Photosynthesis Disease Tools for molecular biology

18. Eukaryotic Cells Key Characteristic: COMPARTMENTALIZATION: Membrane-bound organelles (including the endomembrane system). Nucleus. Plasma membrane.

19. Eukaryote - Animal Cell

20. Eukaryote - Plant Cell

21. The Nucleus Function Control center of cell. Structure Nuclear Envelope 1.2 phospholipid bilayers. 2.Internal bilayer continuous with ER. 3.Nuclear pores that allow selective passage of proteins and RNA.

22. Nuclear Envelope

23. Nuclear Structure (Cntd.) Nucleolus 1.Dark staining region of nucleus. 2.Contains genes that encode rRNA. 3.Function - rRNA synthesis and assembly of ribosomal subunits. Chromosomes DNA and protein (histones).

24. Nucleolus http://cellbio.utmb.edu/cellbio/nucleus3.htm

25. Chromosome Structure

26. Ribosomes Function Protein synthesis. Composition 2 subunits of rRNA and protein.

27. The Endomembrane system Structure Interior membranes that are connected by either: direct physical continuity or vesicular transport Function Compartmentalization, large surface area, and trafficking. Components Endoplasmic reticulum Golgi apparatus Lysosomes

28. The Endomembrane System

30. Endoplasmic Reticulum Structure Lipid bilayer with embedded proteins that forms an intracellular network. Cisternal space. Intracellular Location Continuous with nuclear envelope and concentrated around it.

31. Rough Endoplasmic Reticulum (RER) Structure ER with attached ribosomes. Functions Lipid/membrane synthesis. Synthesis of proteins to be secreted from the cell - determined by the presence of a signal sequence on the polypeptide chain. Synthesis of proteins that will be embedded in the cell membrane or sent to lysosomes.

32. RER Structure

33. Synthesis of Secreted Proteins Signal sequence composed of hydrophobic aa.

34. RER http://trc.ucdavis.edu/mjguinan/apc100/modules/TermsCells&Tissue s/structures/ER.html

35. Smooth Endoplasmic Reticulum (SER) Structure Few attached ribosomes. Functions Lipid/membrane synthesis. Detoxification.

36. SER http://cellbio.utmb.edu/cellbio/ser.htm