Question

why do lysosomes keep their digestive enzymes in membranous sacs?
to help the cell increase protein synthesisto prevent the enzymes from digesting the entire cellto speed up glycolysis and the citric acid cycle

Explanation:

Lysosomes contain digestive enzymes. If these enzymes were not compartmentalized in membranous sacs, they could break down (digest) the cell's own components. Protein synthesis is mainly related to ribosomes and the endoplasmic reticulum. Glycolysis occurs in the cytoplasm and the citric - acid cycle in the mitochondria. The key role of lysosome membrane - bound sacs is to isolate the enzymes from the rest of the cell.

Answer:

to prevent the enzymes from digesting the entire cell