ABSTRACT
Blood is the body’s liquid tissue and major transport system. Tissues have a matrix in which cells are embedded, the matrix for blood being the liquid called plasma. Plasma is mostly water with dissolved substances in it, including minerals like sodium and calcium, nutrients like glucose and amino acids, and a range of different proteins. These proteins include clotting factors, hormones, antibodies, and the blood’s own collection of proteins, like albumin and globulin. The cells (often referred to as formed elements) embedded in this liquid matrix are of three main types: erythrocytes (red blood cells, RBC), leukocytes (white blood cells, WBC) and thrombocytes (platelets). All of these are derived from the same cells found in bone marrow called stem cells, or more specifically haemopoietic stem cells (haem blood, poiesis forming).
