The membrane-bound sac in the cytoplasm containing digestive enzymes that can break down large molecules is called a lysosome.

Here's why:

* Lysosomes are small, spherical organelles found in animal cells.

* They are filled with powerful hydrolytic enzymes capable of breaking down various biomolecules like proteins, carbohydrates, lipids, and nucleic acids.

* This process of breaking down large molecules into smaller ones is called digestion.

* Lysosomes play a crucial role in cellular maintenance and defense by digesting worn-out cell parts, engulfing and destroying invading bacteria, and breaking down cellular debris.

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