<prompt> Low and fixed specific gravity of urine is seen inDiabetes mellitusDiabates insipidusChronic renal failureAcute glomerulonephritis  <response>: Normal specific gravity of urine is 1.015 - 1.025. Theoretical extremes are 1.003 to 1.032. The specific gravity will be decreasedhyposthenuria in excessive water intake, in chronic nephritis, in acute glomerulonephritis, in pyelonephritis and in diabetes insipidus. It is increasedhypersthenuria in diabetes mellitus, in nephrosis and in excessive perspiration. In chronic renal failure, the specific gravity of urine is low and fixed at 1.010 isosthenuria. The earliest manifestation of renal damage may be the inability to produce concentrated urine. Reference : page 317-18 Textbook of Biochemistry D M Vasudevan 6th edition 