significant changes have been introduced in many of the interactive subunits that accommodate the digestion of 12 chemical constituents ( soluble carbohydrate , organic acids , starch , pectin , hemicellulose , cellulose , lipids , soluble protein , insoluble protein , nonprotein n , lignin and ash ) , microbial growth , animal interactions and summary computations .
C0007648
cellulose
C0023705
lignin