Lysosomes are microscopic, sac-like structures suspended in the cytosol of the cell's plasma membrane. The digestive enzymes contained within these organelles are called acid hydrolases. Aside from the breakdown of food particles, the enzymes also digest damaged membranes, aiding in recycling wornout parts of the cell. Another important function of the lysosomes is the prevention of microorganisms from invading the cell. Harmful bacteria and viruses are usually targeted and digested by lysosomes found in white blood cells. Due to their digestive properties, acid hydrolases are isolated from the rest of the cell by the membrane that envelopes the lysosomes. Otherwise, the enzymes will digest all cellular components.
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