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.
Quick Answer. Scientists categorize blood as a connective tissue for two primary reasons. According to Rutgers University, blood originates in embryo in the mesoderm, one of the three primary layers of cells; blood shares this origin with other kinds of connective tissue. And, like other kinds of connective tissue, blood plays a connective role with respect to the systems within the human body.