The cardiovascular system is sometimes called the blood-
vascular, or simply the circulatory, system. It consists of the
heart, which is a muscular pumping device, and a closed system
of vessels called arteries, veins, and capillaries. The heart is a
muscle about the size of a fist, and is roughly cone-shaped. It is
about 12cm long, 9cm across the broadest point and about 6cm
thick. The pericardium is a fibrous covering which wraps around
the whole heart. It holds the heart in place but allows it to
move as it beats. The wall of the heart itself is made up of a
special type of muscle called cardiac muscle.
The heart has two sides, the right side and the left side. The
heart has four chambers. The left and right side each have two
chambers, a top chamber and a bottom chamber. The two top
chambers are known as the left and right atria (singular:
atrium). The atria receive blood from different sources. The left
atrium receives blood from the lungs and the right atrium
receives blood from the rest of the body. The bottom two
chambers are known as the left and right ventricles. The
ventricles pump blood out to different parts of the body. The
right ventricle pumps blood to the lungs while the left ventricle
pumps out blood to the rest of the body. The ventricles have
, much thicker walls than the atria which allows them to perform
more work by pumping out blood to the whole body.
Blood Vessel are tubes which carry blood. Veins are blood
vessels which carry blood from the body back to the heart.
Arteries are blood vessels which carry blood from the heart to
the body. There are also microscopic blood vessels which
connect arteries and veins together called capillaries. There are
a few main blood vessels which connect to different chambers
of the heart.
The aorta is the largest artery in our body. The left ventricle
pumps blood into the aorta which then carries it to the rest of
the body through smaller arteries. The pulmonary trunk is the
large artery which the right ventricle pumps into. It splits into
pulmonary arteries which take the blood to the lungs. The
pulmonary veins take blood from the lungs to the left atrium.
All the other veins in our body drain into the inferior vena cava
(IVC) or the superior vena cava (SVC). These two large veins
then take the blood from the rest of the body into the right
atrium.
These are the major organs of the cardiovascular system
System Organs in the System