2605
The toxic A beta peptides A beta 40 and A beta 42 are produced from the A beta precursor protein ( APP ) , a transmembrane protein which is folded and modified in endoplasmic reticulum ( ER ) .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None