Which of the following is neither reabsorbed nor secreted after glomerular filtaration?

Ans: a (Inulin)Ref: Vasudevan & Sreekumari, 6th edi., Pg. 320Inulin is a polysaccharide made up of fructose unit. It is clinically used to find renal clearance value and GFR. Creatinine is a waste product, from creatine phosphate. This conversion is spontaneous, non enzymatic and is dependent on total muscle mass of the body.It is not affected by diet, age or exercise. 98% creatine pool is in muscle; about 1.6% is converted to creatinine per day which is rapidly excreted.Since the production is continuous, the blood level will not fluctuate much, making creatinine ideal substance for clearance test.Creatinine clearance in males 95-115 ml/minute, females 85-110 ml/minute GFR cannot be measured directly; it is estimated from the clearance.Relationship of GFR with clearanceMechanismResultExampleSubstances filtered; neitherGFR=clearanceInulin, creatininereabsorbed nor excretedclearance <GFRUrea (75 ml/Substances filtered;Clearance>GFRmin) Diodrast,partially reabsorbedSubstances filtered; not reabsorbed but excretedSubstances filtered; completely reabsorbedClearance =0PAH (700 ml/ min) Glucose