1. The Cardiovascular System D
The Cardiovascular System D. Matesic Comprised of: heart and coverings, blood vessels, and innervations
Major function: to transport blood throughout the body for nutrient/waste exchange

2. Cardiovascular System The Heart
Heart-pump for the cardiovascular system; contracts about 100,000 times per day
size – about the size of your fist.
weight – about 250 – 300 grams.
location – Mediastinum.
amount of blood pumped – 5.5 L/min = 800L/day

3. Fig 18.1

4. Coverings of the Heart Pericardium- comprised of:
1) the fibrous pericardium-tough connective tissue layer that : -protects; from injury and infection
-anchors heart
-prevents overfilling; sometimes heart tries to allow too much expansion, fibrous covering helps it from expanding too much.
Fibrous is outside the serous pericardium, very tough.

5. Figure 18.2

6. Coverings of the Heart Pericardium- comprised of:
1) the fibrous pericardium-tough connective tissue layer that : -protects
-anchors heart
-prevents overfilling
2) the serous pericardium
*the visceral layer of the serous pericardium is also called the epicardium of the heart wall
Dense CT.
Epicardium, or layer right before the myocardium

7. Layers of the Heart Wall
Epicardium- visceral layer of serous pericardium
Myocardium-thickest layer comprised of cardiac muscle and supporting CT
Endocardium- whitish sheet of endothelium that lines the heart chambers (interior lining) and valves. Continuous with endothelial lining of blood vessel that enter/leave.
One of the layers of the serous pericardium. Mostly muscle, but has some connective tissue (myo). Endothelium, squamous epithelial cells line the heart, so endocardium is that.

8. Fig 18.4b
Thicker in left ventricle, then right. Because LV pumps throughout whole body, RV only pumps it to the lung, so LV needs more thickness, for more force, to get blood where it needs to go.

9. Chambers of the Heart & major Vessels
Atria-receive blood from vessels
inf. Vena cava
Blood rt. atrium from sup. Vena cava
enters coronary sinus left atrium from – pulmonary vein (4)
Ventricles- dispense blood into vessels
Blood leaves rt. ventricle pulmonary trunk left ventricle aorta
Also, anterior cardiac veins feed into the right atrium.
Leaves RV to pulmonary trunk, LV to aorta.

10. Pathway of Blood through the Heart & Body
Aorta  arteries  arterioles  capillary beds  venules  veins  vena cava  heart  pulmonary trunk  lungs  heart  aorta 

11. Pathway of Blood through the Heart & Body
Systemic Circuit (Systemic circulation; General circulation)
arteries – oxygenated blood
veins – deoxygenated blood
Pulmonary Circuit (Pulmonary circulation)
pulmonary arteries – deoxygenated blood
pulmonary veins – oxygenated blood
All arteries carry blood away from the heart, veins always carry blood to the heart.

12. Coronary Circulation
Fig 18.4b

13. Coronary Circulation *Part of the systemic circulation
Provides oxygenated blood to heart tissue itself and removes unoxygenated blood
Coronary arteries (right and left)-branch from the aorta and run along the atrioventricular groove.
Branch into smaller arteries and arterioles, then into myocardial capillaries that provide oxygenated blood to heart tissue.
Cardiac Veins- collect unoxygenated blood that has passed through capillariy beds and venules of the coronary circulation and enter the heart at the right atrium directly (anterioe cardiac veins) or via the coronary sinus (great, middle and small cardiac veins)
PART OF THE SYSTEMIC CIRCULATION, the capillaries come from a branch of the aorta, that goes back to the heart.

14. Heart Valves Read pp 670-672 up to Homeostatic Imbalance
Describes the valves, and what they do.

15. Physiology of Circulation
Group worksheet, posted after exam.