The pulmonary circulation starts by the :
1) Pumping of deoxygenated blood by the right ventricle
2) Pumping of oxygenated blood by the right ventricle
3) Pumping of deoxygenated blood by left atrium
4) Pumping of oxygenated blood by the left ventricle to the aorta
1) Pumping of deoxygenated blood by the right ventricle