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I/GCSE Biology Question Analysis Topic: Biology - Insulin
Exam Question:
Mention the chemical change that proinsulin undergoes, to be able to act as mature insulin.
Answer:
For I/GCSE Biology, you should know:
Insulin's precursor, proinsulin, is kept in the pancreatic beta islet cells of Langerhans. The C-peptide connects the insulin B and A subunits to form the single polypeptide chain known as proinsulin.
Proinsulin undergoes a chemical transformation that involves the cleavage of the C peptide with the help of type I and type II endoproteases. While proinsulin travels through the Golgi apparatus to be cleaved, this transformation occurs in the Langerhans islet cells.
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Work hard for your I/GCSE Biology examination!
End of analysis. Great!
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_auto/10470115/874775_602893.png)