This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: FMGE 2018, Subject name: Biochemistry
Chaperones are: 
Select and explain. 
A. Purine metabolism mediators, B. Antigen presenting cells, C. Mediators of post-transitional assembly of protein complexes, D. None of the above
C: Mediators of post-transitional assembly of protein complexes
Answer: C: Mediators of post-transitional assembly of protein complexes 
Explanation: CHAPERONES-FOLDING /SHAPE /ASSEMBLY OF PROTEIN POST-TRANSITIONAL CHANGE They facilitate and our the interactions on the polypeptide surfaces to finally give the specific conformation of a protein. Type 1. Hsp70 system- This mainly consists of Hsp70 (70-kDa heat shock protein) and Hsp40 (40-kDa Hsp). These proteins can bind individually to the substrate (protein) and help in the correct formation of protein folding 2. Chaperonin system: This is a large oligomeric assembly which forms a structure into which the folded proteins are inseed. The chaperonin system mainly has Hsp60 and Hspl0.