Mention two advantages of blood as a circulating fluid over water as a circulating fluid.

Blood contains respiratory pigments haemoglobin, which helps in transport of oxygen. This function cannot be carried out by water since water lacks the pigment.

Blood contains various cells like RBCs, WBCs and platelets which perform important functions in the body. These functions cannot be carried out by water since water does not contain any cells.

Blood is more viscous than water.