1. Blood Vessel - Anatomy:
Elastic
Arteries
Muscular
Arteries
Arterioles
Capillaries
Vessel Types:
Heart
1) Arteries (away)
2) Capillaries
3) Veins (toward)
Venules
Veins

2. Structure and function - arterial system.
1/3 Conducting
The aorta & major branches
Thickest
Largest
Elastic tubes
Arteriosclerosis
Atherosclerosis (thickening) = turbulent flow
Balloon or burst (aneurysm)

3. Arterial System 2/3 Distributing 3/3 Arterioles Delivery to organs
More active constriction
Less distensible
Renal/urine - NFP
3/3 Arterioles
Flow determined by arteriole diameter
Constricted = bypassed
Dilated = local flow

4. Capillary Flow Control
Precapillary sphincter
Cuff of smooth muscle fibers
Open = flow
Closed = shunt

6. Venous System. ↑ diameter walls gradually ↔ Vein Valve: Venules→Veins
Larger lumens than corresponding arteries
Reservoirs
65% body’s blood supply
VALVES for backflow
Most abundant in limbs - gravity

7. Blood Vessels: Arteries Arteries Arterioles Capillaries Heart Venules
Carry blood away from heart
Thick-walled:
Smooth muscle / elastic fibers
Withstand high pressure
Venules
Veins

8. Blood Vessels: Arteries Arterioles Arterioles Capillaries Heart
Control distribution of blood flow
Smooth muscle expands / contracts
Under hormone / NS control
Venules
Veins

9. Blood Vessels: Arteries Arterioles Capillaries Capillaries Heart
Nutrients / waste exchanged with cells:
Vessel wall one-cell thick
Blood flow very slow
Materials exit / enter via diffusion
Venules
Veins

10. Blood Vessels: Arteries Arterioles Veins Capillaries Heart Venules
Carry blood towards the heart
Thin-walled; large diameter
65% blood volume in veins
Venules
Veins

11. Blood Vessels: Arteries Arterioles Veins Capillaries Heart Venules
Carry blood towards the heart
Thin-walled; large diameter
65% blood volume in veins
Low pressure system
Blood return to heart assisted by:
1) Valves
2) Skeletal muscle pumps
Venules
Veins

12. Blood Vessels Major arteries. Major veins Aorta Brachiocephalic
Ascending, arch, thoracic, abdominal
Brachiocephalic
Ext. & Int. carotid
Pulmonary
Axillary, brachial, radial, ulnar
Femoral, post. tibial
Major veins
Superior VC
Ext. & int. jugular
Brachiocephalics
Internal & external iliac
Femoral..

13. Heart - Flow Through Heart:
Myocardial
Infarction::
Prolonged blockage
of coronary vessels

14. Circuits
of the
Circulatory
System:

15. Major branches - coronary

16. Coronary Vessels

17. Sequence of Excitation
Heart Physiology:
Sequence of Excitation
Step 1:
Depolarization wave initiated
by sinoatrial node (SA Node)
Step 2:
Impulse to atrioventricular node
(AV Node) where briefly delayed

18. Sequence of Excitation
Heart Physiology:
Sequence of Excitation
Step 3:
Impulse to atrioventricular
bundle and into bundle branches
Step 4:
Impulse spreads throughout
ventricles along Purkinje fibers

19. Intrinsic
Conduction
System:

20. Control
of heart rate: