This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nephrotic Syndrome, Subject name: Pathology
In minimal change disease, albumin is first to appear in urine because: 
Select and explain. 
A. Albumin has high affinity to glomerular basement membrane, B. Albumin has lower molecular weight compared to globulins, C. High albumin:globulin ratio in plasma, D. Active excretion of albumin
B: Albumin has lower molecular weight compared to globulins
Answer: B: Albumin has lower molecular weight compared to globulins 
Explanation: Minimal change disease (Nephrotic syndrome) =Albumin is the first among plasma protein to appear in urine because of: Size of the substance Glomerular filtration layer is thick but porous Any substance <= 4 nm diameter freely filters through this layer. Charge of the substance The sialoproteins like albumin are negatively charged This filtration of a substance like albumin which has diameter of 7 nm is negligible. Albumin has the smallest molecular weight and size out of all the plasma proteins Effacement of foot processes of podocytes leads to loss of recognizable intervening slit diaphragms as well as loss of negative charge of filtration layer The albumin stas appearing in urine as a result of these changes