1. ORGANIZATION OF CARDIOVASCULAR SYSTEM
1.HEART
2.BLOOD VESSELS
A.ARTERIES
B.VEINS
3.CAPILLARIES 1

2. Lungs Pulmonary capillaries Pulmonary veins Pulmonary circulation
arteries
Right
side of
heart
Left
side of
heart
Systemic
arteries
Systemic
veins
FIGURE 9-1: Pulmonary and systemic circulation in relation to the heart. The circulatory system consists of two separate vascular loops: the pulmonary circulation, which carries blood between the heart and lungs; and the systemic circulation, which carries blood between the heart and organ systems.
Systemic
circulation
Systemic
capillaries
= O2-rich blood
Organ
systems
= O2-poor blood
Fig. 9-1, p. 242 2

3. MAIN FUNCTIONS OF THE CIRCULATORY SYSTEM
Transport and distribute essential substances to the tissues.
Remove metabolic byproducts.
Adjustment of oxygen and nutrient supply in different physiologic states.
Regulation of body temperature.
Humoral communication.

4. Distribution of Blood in the Circulatory System
67% IN THE SYST. VEINS/VENULES
5% IN THE SYSTEMIC CAPILLARIES
11% IN THE SYSTEMIC ARTERIES
5% IN PULMONARY VEINS
3% IN PULMONARY ARTERIES
4% IN PULMONARY CAPILLARIES
5% IN HEART ATRIA/VENTRICLES

5. Left atrioventricular (AV) valve Right atrium
Superior vena
cava (from head)
Aorta
Left pulmonary
artery
Right pulmonary
artery
Left pulmonary
vein
Right
pulmonary vein
Left atrium
Pulmonary
semilunar valve
Left atrioventricular
(AV) valve
Right atrium
Right atrioventricular
(AV) valve
Aortic semilunar
valve
FIGURE 9-2: Blood flow through and pump action of the heart. (a) Blood flow through the heart.
Inferior vena cava
(from body)
Left ventricle
Interventricular
septum
Right ventricle
Arrows indicate direction
of the blood flow.
= O2-rich blood
= O2-poor blood
Fig. 9-2a, p. 243 5

6. Interventricular septum Inferior vena cava
Aorta
Pulmonary artery
Superior vena cava
Pulmonary valve
Pulmonary veins
Pulmonary veins
Left atrium
Left AV valve
Right atrium
Aortic valve
Chordae tendineae
Right AV valve
Papillary muscle
FIGURE 9-4: Heart valves. (a) Longitudinal section of the heart, depicting the location of the four heart valves.
Left ventricle
Right ventricle
Interventricular septum
Inferior vena cava
Fig. 9-4a, p. 245 6

7. Pressure Drop in the Vascular System
ELASTIC TISSUE
MUSCLE
LARGE ARTERIES
SMALL ARTERIES
MEAN PRESSURE
ARTERIOLES
CAPILLARIES
VENULES &VEINS
LARGE
SMALL
LARGE
INSIDE DIAMETER 7