What is urine ? Give the composition of urine

Urine is a pale yellow coloured and transparent fluid.

(a) The pale yellow colour is due to pigment urochrome produced by the breakdown of haemoglobin from
worn out RBCs.
(b) Normal urine contains about 95% water, 2% electrolytes (ions of salts, mainly chlorides,sulphates, bicarbonates of sodium, potassium etc.), 2.6% urea, 0.3% uric acid and traces of creatinine, afnmonia, some pigments, hormones, allantoin and hippuric acid.