1. Activity #10: Vessels and Circulation
Chapter 23 – McKinley et al., Human Anatomy, 4e.
Objectives:
Observe and sketch histology slide of an artery and a vein and identify structures on each.
Identify structures and vessels involved in pulmonary circulation on cadavers and classroom models.
Identify structures and vessels involved in systemic circulation (by region) on cadavers and classroom models.
Compilation: Lisa Radmall

2. Vessels: Layers of Vessel Wall
Tunica intima
Thin, innermost layer of vessel wall.
Endothelium and thin layer of areolar connective tissue.
Tunica media
Middle layer of vessel wall, thickest layer in arteries.
Smooth muscle cells, circular arrangement for vasoconstriction when contracted and vasodilation when relaxed.
Tunica externa
Outermost layer of vessel wall, thickest layer in veins.
Areolar connective tissue, helps to anchor vessels to other structures.

3. Vessels: Layers of Vessel Wall
Fig. 23.1

4. Vessels: System Comparison
Fig. 23.3

5. Vessels: Histology
Fig. 23.2

6. Vessels: Histology

7. Vessels: Identification on Cadavers
Arteries
Round shape
Collapse when ‘pinched’ (hollow lumen)
Rebounds to round shape
Veins
Flat shape
Usually collapsed
Often dark in color
Nerves
Does not collapse when ‘pinched’ (contains nerve fibers)

8. Circulation: Overview
Pulmonary Circulation carries deoxygenated blood from right ventricle through pulmonary trunk and ultimately to capillary beds of the lungs, then carries oxygenated blood back through the pulmonary veins to the left atrium.

9. Circulation: Overview
Systemic circulation carries oxygenated blood from the left ventricle of the heart through the aorta, ultimately to the capillary beds of systemic body organs, then carries deoxygenated blood back to the right atrium
Note: Coronary arterial and venous circulation is also part of systemic circulation and was covered in the previous laboratory activity.

10. Pulmonary Circulation
Left
pulmonary
artery
Right
pulmonary
artery
Left
Pulmonary
trunk
Right
pulmonary
veins
Left
pulmonary
capillaries
Right
pulmonary
capillaries

11. Systemic Circulation: Arterial Flow Away From Heart
Aorta – Carries oxygenated blood from the left ventricle to body organs and tissues.
Ascending aorta
Left & right coronary arteries. Supplies heart muscle.
(A) Aortic arch - ABCs
(B) Brachiocephalic trunk
(C) Left common carotid artery
(S) Left subclavian artery
Descending Aorta
Descending thoracic aorta (above diaphragm)
Descending abdominal aorta (below diaphragm)
(C) Left Common Carotid Artery
Pulmonary
trunk
(A) Ascending
Aorta
(B) Brachiocephalic trunk
(S) Left Subclavian Artery
Aortic Arch

12. Systemic Circulation: Venous Return to Heart
Superior vena cava
Returns deoxygenated blood from head, neck, thorax, and upper limbs to right atrium.
Inferior vena cava
Returns deoxygenated blood from the lower limbs, abdomen, and perineum to right atrium.
Coronary sinus
Returns deoxygenated blood from heart muscle to right atrium.

13. Systemic Circulation: Blood Flow to/from Heart
Fig. 22.5b

14. Circulation: Head and Neck – Arterial Supply
Fig a

15. Circulation: Head and Neck – Arterial Supply
Fig a

16. Circulation: Head and Neck – Venous Drainage
Fig b

17. Circulation: Head and Neck – Venous Drainage
Fig b

18. Circulation: Ventral Cavity – Arterial Supply
Fig

19. Circulation: Ventral Cavity – Celiac Trunk
Fig a

20. Circulation: Ventral Cavity – Mesenteric Arteries
Fig b

21. Circulation: Ventral Cavity – Venous Drainage
Fig

22. Circulation: Hepatic Portal System
A portal system consists of two capillary beds in a series connected by a portal vein.
The hepatic portal system is a venous network that drains the GI tract and shunts blood to the liver for absorption and processing of transported materials. (p.703) Blood drained from the abdominal organs is processed in the liver’s wide sinusoid capillaries before returning to systemic venous circulation.
(1st capillary beds)
(2nd capillary bed)

23. Circulation: Hepatic Portal System
Fig

24. Circulation: Hepatic Portal System Mnemonic
Visual Mnemonic: The location of the main veins of the hepatic portal system seem to form a visual “chair” when isolated.
Table 23.3

25. Circulation: Arterial Supply to Upper Limb
**All vessels are paired**
(right and left sides)
Fig a

26. Circulation: Venous Return to Upper Limb
**All vessels are paired**
(right and left sides)
Fig b

27. Circulation: Arterial Supply to Lower Limb
**All vessels are paired**
(right and left sides)
Fig a

28. Circulation: Venous Return to Lower Limb
**All vessels are paired**
(right and left sides)
Fig b

29. Circulatory System - Summary

30. Circulatory System – Plastinated Vessels

31. Image References
Pulmonary Circulation: