Answer: The answer is substrate
Step-by-step explanation:
The SUBSTRATE for beta-glucocerebrosidase is glucocerebroside. In this case glucocerebroside, the substrate is broken down to ceramide (sphingosine + fatty acid) and 3 molecules of galactose in a reaction catalyzed by the enzyme beta-glucocerebrosidase.
Deficiency of this enzyme lead to inability of ceramide to be cleaved from the substrate resulting in accumulation of the substrate in organs of the body such especially lungs and bone marrow in a condition called Gaucher's disease.
Thus, substrate is the answer