Blood is a connective tissue (Sedava, 2010)composed of a liquid portion called plasma and a cellular portion consisting of various cell and cell fragments. The cellular components are red blood cells, white blood cells and platelets. Most of the cells in the blood are erythrocytes ( red blood cells) and their main function is to transport respiratory gases (Kent, 2000).Platelets play an important role in blood clotting (Kent, 2000).Tissue fluid is similar to blood but it does not contain most of the cells found in the blood nor does it contain plasma nutrients. Tissue fluid is the fluid that surrounds the tissue and cells. The role of tissue fluid is to transport nutrients from the blood to the cells i.e. oxygen and to carry carbon dioxide and other waste substances back to blood. Plasma comprises many dissolved substances such as oxygen, carbon dioxide, salts, glucose, fatty acids, amino acids, hormones and plasma proteins and other waste back to the blood. (Beckett, 1986)
Deoxygenated blood which comes from tissues return to the right atrium of the heart via (Pauline Lowrie, 2008) the vena cava and passes into the right ventricle and gets pumped to the lungs through the pulmonary artery. Oxygenated (Pauline Lowrie, 2008) blood comes from the lungs via the left atrium of the heart into the left ventricle and it gets pumped to the rest of the body via the major vein the aorta.
Tissue fluid is primarily there to give-and-take oxygen and glucose is dissolved in It, so that the cells can take that in (Kent, 2000) Red blood cells and larger molecules such as plasma protein remain in the capillary (Sedava, 2010) and the proteins use the osmotic pull in water to keep it in the capillary (Pauline Lowrie, 2008) and this force is smaller than the hydrostatic push of the blood pressure which means they are an overall net push of water and solutes out through the capillary walls which consist of a single layer of thin endothelial cells (Pauline...