Also see user session. In telecommunication, a session is a series of interactions between two communication end points that occur during the span of a single connection.
The path of blood through the heart begins with the right atrium receiving blood, which has circulated through most of the body. This blood is relatively low in oxygen because most of it has already been delivered to different organs and tissues.
Part 3: Circulatory Pathways: Blood Vessels of the Body. Two distinct pathways travel to and from the heart: pulmonary circulation runs from the heart to the lungs and back to the heart; systemic circulation runs to all parts of the body before returning to the heart.