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 is essential. In addition to carrying fresh oxygen from the lungs and nutrients to your body's tissues, it also takes the body's waste products, including carbon dioxide, away from the tissues. This is necessary to sustain life and promote the health of all the body's tissues. There are three main types of blood vessels: Arteries. Arteries carry oxygen-rich blood away from the heart to all of the body's tissues. They branch several times, becoming smaller and smaller as they carry blood farther from the heart and into organs. Capillaries.