1. Cell Junctions and extra cellular matrix II chapter 19

2. Desmosomes and hemidesmosomes both link to intermediate filaments

3. Cadherins also bind intermediate filaments together

5. Integrins link extracellular matrix to cytoskeleton

6. Size of gap junction channel can be determined with fluorescent molecules of different sizes

7. A Gap junction connexon is made up of 6 transmembrane connexin subunits

8. Images of gap junctions

9. The permeability of gap junctions can be regulated dopamine treatment reduces permeability of gap junctions to a fluorescent dye

10. Summary of cell junctions found in the cell

12. In plant cells plasmodesmata perform many of the same functions as gap junctions

13. View of plasmodesmata

14. Structure of Cadherin – responsible for cell to cell adhesion in vertebrate cells

15. Ca 2+ is required to establish cell to cell connection through cadherin

16. Three mechanisms that mediate cell-cell adhesion least common cadherins

17. Cadherins allow cells to sort themselves

18. Catenins join cadherins to actin filaments in adherence junctions

19. Summary of junctional and non-junctional adhesive mechanisms

20. Cells surrounded by extracellular matrix

21. Cross sectional view of intestinal wall

22. Connective tissue underlying the epithelium contains a variety of cells and extracellular matrix components

23. Fibroblasts surrounded by collagen fibrils

24. Glycosaminoglycan (GAG) chains occupy large amounts of space and form hydrated gels

25. Hyaluronan, a simple GAG, occupies a large amount of space, thereby providing mechanical support

26. Repeating disaccharide unit of hyaluronan

27. GAG and its core protein form proteoglycan

28. Comparison of proteoglycans with a ribonuclease

29. picture of aggrecan aggregate, a large proteoglycan

30. structure of Aggrecan aggregate

31. Collagen fibril embedded in proteoglycan molecules

33. Fibroblast surrounded by collagen fibrils

34. Collagen fibrils in tadpole skin This arrangement is also found in bone and the cornea

35. Elastic fibers in a dog’s aorta

36. Each elastin protein in the network can expand and contract as a coil

37. Fibronectin is an extracellular protein that helps cells attach to the matrix

38. Connective tissue underlying the epithelium contains a variety of cells and extracellular matrix components

39. basal lamina in the cornea of a chick’s embryo

41. A model of the basal lamina

42. Cross Section of Kidney

43. Filtration is one step in urine formation

44. Structure of Nephrons

45. Inside Bowman’s Capsule

48. Basal Lamina plays an important role in filtration