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.
Blood cells are formed by a process called hematopoiesis. Blood is circulated by the heart through the vascular system (veins/arteries), carrying oxygen and nutrients to and waste mate-rials away from all body tissues. The average person has about 5 liters (more than a gallon) of blood in their body.1.lood is circulated by the heart through the vascular system (veins/arteries), carrying oxygen and nutrients to and waste mate-rials away from all body tissues. The average person has about 5 liters (more than a gallon) of blood in their body.1.