And these two processes, one taking place in the right pump and the other one taking place in the left pump take place simultaneously at the same exact moment in time. So here we have the contraction of our right ventricle and the contraction of the left ventricle that takes place at the same exact moment in time. And if we examine these three stages these three stages basically take place over and over and over. And this creates a unidirectional and a continuous flow of blood not only inside the four chambers of the heart but also inside the entire cardiovascular system of our body. So, once again, in stage number one we have the right atrium and our left atrium that are fully relaxed and they are accepting, they are receiving blood inside those atrium. The right atrium is receiving deoxnated blood while our left atrium is receiving oxygenated blood.