1189
Passive stiffness , on the other hand , is thought to stem from non - muscle component of the airway wall , especially the collagen / elastin fibrous network of the extracellular matrix within which the muscle cells are embedded .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None