CHAPTER 5: THE RENAL SYSTEM: ALSO A SOURCE FROM GENERAL PHYSIOLOGY

First, we recall our aquatic origin showing how, steadily and very slowly, evolution brought us to the present state, where the intellect has become the central core — the kernel — governing all our steps immersed in the internal sea. The renal functions take place within it, giving us freedom to move about and beyond. Convolution and deconvolution are thereafter introduced, as mathematical tools, to find the renal retention function, essential physiological concept derived from renography. Finally, the renin–angiotensin–cardionatrine system is dealt with, even though some reader may complain it had better belong to the endocrine area.