The intima of elastic arteries is thicker than muscular arteries. The media of elastic arteries contains irregular elastic tissue. Smooth muscle nuclei are present without defined cytoplasm, and smooth muscle produces collagen and elastic tissue but does not contract. Elastic arteries and large veins have more vasa vasorum than muscular arteries to oxygenate blood. Elastic tissue converts intermittent blood flow to continuous flow via expansion and recoiling. Veins have thinner media than adventitia and contain mainly collagen. Their functions are low resistance collection and low pressure storage.

1. ١

2. ٢

3. The intima of elastic artery is thicker than the muscular artery
٣

4. Media: - the irregular line is elastic tissue
The nucleus for smooth muscle (not fibroblast or fibrocyte) with ill-defined
cytoplasm
the smooth muscle is important to produce collagen and elastic, not to
make contraction!!!
٤
Media: - the irregular line is elastic tissue
The nucleus for smooth muscle (not fibroblast or fibrocyte) with ill-defined
cytoplasm
the smooth muscle is important to produce collagen and elastic, not to
make contraction!!!

5. The vasa vasorum is more in elastic artery than muscular artery and more
in the large vein because most of the blood inside it is poorly oxygenated
٥
The vasa vasorum is more in elastic artery than muscular artery and more
in the large vein because most of the blood inside it is poorly oxygenated

6. What is the most predominant tissue here? and why?
Elastic tissue, to convert the intermittent blood flow to continues by
expansion and recoiling.
Collagen and smooth muscle for strength
٦
What is the most predominant tissue here? and why?
Elastic tissue, to convert the intermittent blood flow to continues by
expansion and recoiling.
Collagen and smooth muscle for strength

7. ٧

8. The adventitia contains mostly collagen and little elastic
٨

9. ٩

10. ١٠

11. In the artery the media is thicker than the adventitia while it is the opposite
in vein
The vein wall contains mainly collagen
١١
In the artery the media is thicker than the adventitia while it is the opposite
in vein
The vein wall contains mainly collagen

12. Characteristic of veins
1) low resistance collecting system
2) Low pressure storage system
١٢
Characteristic of veins
1) low resistance collecting system
2) Low pressure storage system

13. ١٣

14. Well defined internal & external elastic laminae
١٤

15. ١٥

16. ١٦

17. ١٧

18. ١٨

19. Medium sized vein = capacitant vein
١٩

20. What is the main function of venules? Diapedese
Arteriole gives met-arteriole which gives capillary then gives venule
Between the meta-arteriole and the capillary there is precapillary sphincter
The sphincter and the met-arteriole poorly innervated by sympathetic but
expand and narrow by local metabolite.
٢٠
What is the main function of venules? Diapedese
Arteriole gives met-arteriole which gives capillary then gives venule
Between the meta-arteriole and the capillary there is precapillary sphincter
The sphincter and the met-arteriole poorly innervated by sympathetic but
expand and narrow by local metabolite.

21. ٢١

22. ٢٢

23. ٢٣

24. ٢٤

25. ٢٥

26. ٢٦

27. ٢٧

28. ٢٨

29. ٢٩

30. ٣٠

31. ٣١

32. ٣٢

33. ٣٣

34. Thicker
not contractile = no myofibrils
Much glycogen
No T tubule system
Beneath endocardium
٣٤
Thicker
not contractile = no myofibrils
Much glycogen
No T tubule system
Beneath endocardium

35. ٣٥

36. ٣٦