Introduction of cardiovascular

The circulatory system :
Lecture Objectives
By the end of this lecture, students are expected to:
1.Summarize the structural layers of the walls of all four heart chambers .
3. Outline the histological features of the pericardium, endocardium.
4. Outline of the innate cardiac conducting system.
5.Differntiate between the layers of arteries .
6. summarize the differences between types of veins .
7. Differentiate between the types of capillaries.
Introduction:
The circulatory system pumps and directs blood cells and substances carried in blood to all tissues of the body.
It includes both the blood and lymphatic vascular systems, The blood vascular system , or cardiovascular system , consists of the following structures:
? The heart propels blood through the system.
? Arteries , a series of vessels efferent from the heart that become smaller as they branch into the various organs, carry blood to the tissues.
? Capillaries , the smallest vessels, are the sites of O 2 , CO 2 ,
nutrient, and waste product exchange between blood and tissues. Together with the smallest arterial and venous branches carrying blood to and from them, capillaries in almost every organ form a complex network of thin, anastomosing tubules called the microvasculature or
microvascular bed.
? Veins result from the convergence of venules into a system of larger channels that continue enlarging as they approach the heart, toward which they carry the blood to be pumped again.