From the starting of the animal kingdom itself as we move along the line of phyla we observe that right from within a single cell to amongst many cells to amongst organs there is a transport system. Every cell needs nutrition and oxygen. We, humans, being a part of Vertebrata, Mammalia we have a complex transport system in our bodies- Blood . Blood is the transport fluid of our bodies. It carries not just nutrition but also oxygen, carbon dioxide, water, waste products, hormones, etc. Such an important connective tissue of our bodies that travels throughout but in a closed system (only within veins and arteries) and double circulation (from different parts of the body to heart, from the heart to lungs, from lungs to heart- Blood comes twice into the heart) which ensures blood which is oxygenated and deoxygenated is separated and can be efficiently oxygenated. Illustration: Red Blood Corpuscle. Blood consists of plasma and cellular components. 1. Plasma is t...
