How is the left ventricle important to the systemic circulation?
Its contraction pushes blood into the aorta and then it goes to
all the body tissues in the systemic circuit down to the capillary
level. From here, the blood is picked up by the capillaries that
lead to venules, and then to veins and brought back to the heart's
right atrium. This is the end of the systemic circuit and the
beginning of the pulmonary circuit starts in the right atrium.