1480
The effect of diffusion limitation was quantified in terms of the ratio O2 uptake / O2 requirement ( = fraction of cross - sectional area supplied with O2 ) , assuming local O2 requirement per unit volume to be constant and independent of PO2 at PO2 greater than 0 .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
 Entities:  
Answer:
 None