1. Lecture 2 Outline (Ch. 6) I.Prokaryotes vs Eukaryotes II.Organelles Overview III.Endomembrane System IV.Energy Organelles VI.Cytoskeleton VII.Extracellular Structures VIII.Summary

2. Prokaryotes vs. Eukaryotes Prokaryotes: - Archaea and Bacteria nucleoid (DNA) ribosomes plasma membrane cell wall capsule pili flagella 1-10μm

3. Eukaryotes: - Protists, Fungi, Plants, Animals - Several organelles - Larger Prokaryotes vs. Eukaryotes 10-100μm 333 μm

4. Eukaryotic Organelles

5. Eukaryotic Organelles Nucleus – genetic material chromosomes (DNA + proteins) nuclear envelope -double bilayer nuclear pores nuclear matrix

6. Nucleolus makes rRNA Chromosomes/DNA Eukaryotic Organelles Nucleus – genetic material

7. Ribosomes – protein synthesis Made in nucleolus Bound or free Two subunits Made of RNA & proteins Free – make cytoplasmic proteins

8. Bound Ribosomes Build Membrane & Exported Proteins Ribosomes – protein synthesis

10. Eukaryotic Endomembrane System Endomembrane System – shipping and transport in cells

11. Lipid Synthesis Detoxify Drugs Membrane Factory Adds Carbohydrates to Glycoproteins

12. Endomembrane System

13. 1. Endoplasmic reticulum (e.r.) Two types – rough & smooth Endomembrane System ”bleb” off in vesicles Extensive membrane Continuous with nuclear envelope Inside is the lumen

14. 2. Golgi apparatus Shipping and receiving Flattened sacs Vesiscles – transport around cell Protein modification & direction Endomembrane System

15. 3. Lysosomes Cellular digestion Not in plants Bleb off Golgi or cell membrane Acidic inside – break down (a) food particles or (b) old cell parts - both by HYDROLYSIS Endomembrane System “phagocytosis”“autophagy”

16. Plant cell 4. Vacuoles Storage/maintenance compartments Food vacuole Water vacuole -contractile vacuole Disposal for by-products Central vacuole Animal cell Endomembrane System

17. 5. Plasma membrane Lipid bilayer – selective barrier Membrane-associated proteins – depend on cell type Endomembrane System Present in ALL CELLS

18. Mitochondria Harvest Chemical Energy ribosomes and own DNA

19. ribosomes and own DNA! Chloroplast Light to Chemical Energy

20. Question: Why do mitochondria and chloroplasts have their own DNA and ribosomes?

21. Cytoskeleton - Eukaryotes Thick! Thin! Intermediate filaments – Intermediate!

22. Radiate from center Internal transport, motility, cell division Cytoskeleton - Microtubules Inside flagella Inside cilia Make centrioles

23. Localized at membrane Cell movement Cytoskeleton - Actin filaments Muscle fiber contraction Pseudopodia Cytoplasmic streaming (plants)

24. Throughout cell to support shape make up nuclear lamina, and mesh outside nucleus Example: keratins Cytoskeleton - Intermediate filaments fibers linked into sheets, then ropes

25. Extracellular Spaces – Cell wall In plants - made of cellulose Thick cells connected through cell wall plasma membrane cell wall

26. Animal cells - glycoproteinsEx. collagen ECM – cell communication, movement Extracellular Spaces – Extracellular Matrix (ECM)

27. Animal cells - three types 1.tight junctions (no-leak) 2. desmosomes (flexible) 3. gap junctions (communication) Extracellular Spaces – Junctions

28. OrganelleFunctionPart of Endomembrane System? In Bacteria? Plants? Animals? NucleusStore genetic infonoP, A Ribosomes Rough e.r. Smooth e.r. Golgi Plasma Membrane Lysosomes Vacuoles Cytoskeleton Cell Wall ECM