Vascular Biology, Structure and Function
2.1.1 The Circulatory System
The heart, the arterial
systems, the venous systems
microcirculatory systems, coupled with neuro-humoral influences form
the entire circulation. Each is an important functional complement that
the circulatory system cannot be effectively described by one part alone.
By virtue of the distributing vascular trees, oxygen, humoral agents, and
nutrients are transported to the vital parts of the body and the waste
products are removed. The heart provides the necessary energy.
In terms of the general structure components, Fig.
provide an overview of the connectivity of the circulation.
The heart in mammalian species has four chambers, the
and right atria. The left ventricle pumps blood into
the aorta and perfuse the systemic arterial system and the right ventricle
pumps into the main pulmonary trunk and perfuse the pulmonary arterial
The shape of the left ventricle is in-between conical and semi-
ellipsoidal with its narrow end forming the apex of the heart. These
shapes, as well as cylinder and sphere, have been used in ventricular
modeling. The left ventricular wall is about three times as thick as the
right ventricle, thus
able to develop a much higher pressure. The thick
interventricular septum, separating the left and right ventricles,