This is a fill-in-the-blank problem. Frankly this is just a memorization exercise. I remember the C-peptide is in the middle and the remaining two chains were linked by the disulphide bonds. What I don't remember is which part is A and which part is B, so I just tried, failed once, thanksfully I have another try so I make it :)
I was confused with the "Binding Capacity" phrase, not sure what that means without a context. For this problem in particular, it seems to be irrelevant. The way I interpreted that is that in the wild type, the Proinsulin level is low, persumably we are measuring the concentration at location where the proinsulin is expected to be cleaved (e.g. in blood plasma), so the mutant has problem to be cleaved. So a reasonable answer would be "Within one of the splicing sites", and that's correct.
Given the last problem is correct, the only sensible solution for this one is "Within the A chain or the B chain". Now the "Binding capacity" make sense, it means the ability of the hormone to bind its receptor. If the A-chain or B-chain is not changed in the previous problem, it probably is still capable to bind the receptor.
I respectfully disagree the answer given on EDX for this one.
The mutation is occurring on the splicing site - therefore, we should be in a situation similar to problem 14, with elevated proinsulin level. Instead of that, the given correct answer is lowering binding affinity for the insulin receptor, that's just sound strange to me.
It is $ \alpha-$ chymotrypsin - chymotrypsinogen is the zymogen and trypsin is the agent used for the cleaving.
The first few amino acid starting from the N-terminal is the signal peptide, they are used to direct the protein to different organelles. Therefore the answer is
They most likely are targeted to different cellular locations.
If chymotrypsin were translated into active form inside the pancreas, it would start digesting the protein inside the pancreas. Therefore the answer is
Pancreatitis (breakdown of pancreas cells)
The C peptide is the short peptide chain that connects insulin's A chain and B chain.
This is yet another fill-in-the-blank problem, the question above has the answer is it already.
Thrombin cleaves fibrinogen.
Factor VII and tissue factors are the extrinsic pathway.
Factor XI is the intrinsic pathway.
Both AntiThrombin (AT) and Thrombomodulin inhibit thrombin.
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