The circulatory system has the lymphatic system, which circulates lymph, It is known as the cardiovascular system or the vascular system, It is a vital organ system that delivers essential substances to all cells...
Blood is the principal medium in the transport process, Its colour is a red viscous liquid, PH equals 7.4 (weak alkaline), and Volume is 5 – 6 liters of blood on average, The structure...
Animals obtain their requirements of energy in the form of food, after its digestion, the soluble food substances are absorbed, but still remains the problem of their transport and distribution to the various tissues...
