Advanced Placement (AP) Biology Practice Exam

What is the function of a lysosome?

1. To store genetic information

2. To perform photosynthesis

3. To digest macromolecules

4. To synthesize proteins

The correct answer is: To digest macromolecules

Lysosomes serve an essential function in cellular biology by digesting macromolecules. These organelles contain hydrolytic enzymes capable of breakdown various biomolecules, such as proteins, nucleic acids, carbohydrates, and lipids. This digestion process is crucial for several cellular processes, including nutrient recycling, waste processing, and cellular repair. Lysosomes can also participate in autophagy, where they digest damaged organelles, allowing the cell to renew itself and maintain homeostasis. This ability to break down and recycle cellular components is fundamental to cellular health and function, highlighting the vital role lysosomes play in the life of a cell. Other functions mentioned, such as storing genetic information or synthesizing proteins, are not associated with lysosomes but rather with the nucleus and ribosomes, respectively. Photosynthesis is specific to chloroplasts in plant cells and does not involve lysosomal function.