1. Cardiovascular System
A closed system of the heart and blood vessels
Objectives:
Describe the location of the heart in the body and identify the heart chambers, sounds, and valves. Trace the pathway of blood through the heart and compare the functions of the heart chambers on the right and left sides.
Compare the pulmonary and systemic circuits.

2. The Cardiovascular System
The function of the cardiovascular system
TRANSPORTATION
deliver oxygen
deliver nutrients
movement of hormones
remove carbon dioxide
remove urea
remove other waste products

3. Blood: the mechanism for transport of these materials
Blood vessels: tubes through which materials are transported
Heart: the force that keeps materials circulating

4. The Heart
Location
Thorax between the lungs in the inferior mediastinum
Orientation
Pointed apex (tip) directed toward left hip
Base (where the blood vessels emerge) points toward right shoulder
About the size of your fist
Hollow
Cone shaped

5. The Heart: Coverings Pericardium—a double-walled sac
1. Fibrous pericardium is loose and superficial
for protection
to hold the heart in place

6. The Heart: Coverings
Serous pericardium (deep to the fibrous pericardium)
2 layers
a. Visceral pericardium
Next to heart; also known as the epicardium
b. Parietal pericardium
Outside layer that lines the inner surface of the fibrous pericardium
Serous fluid fills the space between the layers of pericardium

7. 1. Heart
2. Fibrous pericardium
3. Parietal layer of serous pericardium
4. Visceral layer of serous pericardium
5. Pericardial space
6. Pleural cavity and lung

8. The Heart: Heart Wall 3 layers Epicardium (AKA: visceral pericardium)
Outside layer
Connective tissue layer
Myocardium
Middle layer
Mostly muscle
Endocardium
Inner layer
Endothelium

9. The Heart: Chambers Right and left side act as separate pumps
Four chambers
Atria (plural)
Receiving chambers
Right atrium
Left atrium
Ventricles
Discharging chambers
Right ventricle
Left ventricle

10. Differences in Right and Left Ventricles
Left ventricle is visibly more muscular
It is responsible for pushing the blood out of the heart and into the vessel systems that carry blood to the entire body
Figure 11.4

11. The Heart: Septa Tissue dividing the chambers
Named based on their location
Interventricular septum
Separates the two ventricles
Interatrial septum
Separates the two atria

12. The Heart: Valves
Allow blood to flow in only one direction to prevent backflow
4 valves
Atrioventricular (AV) valves
between atria and ventricles
1. Bicuspid (AKA: mitral) valve (left side of heart)
2. Tricuspid valve (right side of heart)

13. The Heart: Valves Semilunar valves between ventricle and artery
3. Pulmonary semilunar valve
4. Aortic semilunar valve

14. The Heart: Valves AV valves (Tricuspid/Bicuspid)
Anchored in place by chordae tendineae (“heart strings”) which attach to papillary muscle to keep them from turning inside out
Open during heart relaxation and closed during ventricular contraction

15. The Heart: Valves Semilunar valves
Closed during heart relaxation but open during ventricular contraction
Notice these valves operate opposite of one another to force a one-way path of blood through the heart

16. 2 Main Types of Circulation
1. Systemic circulation
Blood flows from the left side of the heart through the body tissues and back to the right side of the heart

17. 2 Main Types of Circulation
2. Pulmonary circulation
Blood flows from the right side of the heart to the lungs and back to the left side of the heart

18. Systemic and Pulmonary Circulations
Figure 11.3

19. The Heart: Associated Great Vessels
Arteries
Aorta
Leaves left ventricle
Pulmonary arteries
Leave right ventricle

20. The Heart: Associated Great Vessels
Veins
Superior and inferior venae cavae
Enter right atrium
Pulmonary veins (four)
Enter left atrium

21. The Heart: Summary
Figure 11.2c

22. The Heart: Associated Great Vessels
Figure 11.2c

23. Blood Flow Through the Heart
Superior and inferior venae cavae dump blood into the right atrium
From right atrium, through the tricuspid valve, blood travels to the right ventricle
From the right ventricle, blood leaves the heart as it passes through the pulmonary semilunar valve into the pulmonary trunk
Pulmonary trunk splits into right and left pulmonary arteries that carry blood to the lungs

24. Blood Flow Through the Heart
Oxygen is picked up and carbon dioxide is dropped off by blood in the lungs
Oxygen-rich blood returns to the heart through the four pulmonary veins
Blood enters the left atrium and travels through the bicuspid valve into the left ventricle
From the left ventricle, blood leaves the heart via the aortic semilunar valve and aorta

25. Practice!!
Practice Labeling