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 vessels and muscle tissue are also derived from mesenchyme, so that blood vessels and muscles are always embedded within connective tissue. Nerves grow out into connective tissue from the neuroectodermally derived central nervous system, so nerves are also embedded in connective tissue.