<prompt> A patient reports a change in colour of urine on air exposure. All are true about the condition shown below except:Blackening of urine is accelerated on exposure to sunlightAlkapton bodies are deposited in intervertebral discUrine Benedicts test is negativeNitisinone is an inhibitor of the enzyme 4- hydroxy phenyl pyruvate dioxygenase  <response>: Ans. C. Urine Benedicts test is negativea. Alkaptonuria leads to blackening of urine which is accelerated by exposure to sunlight and oxygen.b. The alkapton bodies are polymers of Homogentisic acid and are deposited in vertebral discs, cartilage of nose, pinna.c. Benedicts test is positive with muddy yellow precipitated. Nitisinone, is an inhibitor of the enzyme 4 hydroxyphenylpyruvate dioxygenase that produces Homogentisic acid. 