This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: JIPMER 2018, Subject name: Physiology
Glomerular filtration barrier does not permit 
Select and explain. 
A. 4000 daltons, B. 400 daltons, C. 40000 daltons, D. 40 daltons
C: 40000 daltons
Answer: C: 40000 daltons 
Explanation: Glomerular filtration barrier - it has: - Glomerular capillary - has endothelial cells which are fenestrated Basement membrane Layer of epithelial cells (podocytes) Characteristics of the filtration barrier: - Has high filtration rate. Capillary endothelium is perforated by thousands of small holes called fenestrae. The basement membrane contains negatively charged sialo proteins; they repel negatively charged plasma proteins. Glomerular capillary has epithelial cells, these cells are not continuous but have long footlike processes (podocytes). Podocytes are separated by filtration slit pores, through which the filtrate moves. The epithelial cells also have negative charge. Pores of glomerular capillary are thought to be about 4 - 8 mm. (40- 80 angstroms) Filtration is both size selective & charge selective.