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Human Body Study

Lysosomes

The cell’s recycling and waste-disposal units — small membrane sacs filled with powerful digestive enzymes.

Schematic of a generalized animal cell A labelled cross-section of a generalized animal cell. Each label links to the article for that part: the cell membrane, cytoplasm, nucleus, mitochondria, ribosomes, endoplasmic reticulum, Golgi apparatus, lysosomes and cytoskeleton. rough ER smooth ER Cell membrane Mitochondria Nucleus Endoplasmicreticulum Lysosomes Cytoskeleton Cytoplasm Ribosomes Golgi apparatus A generalized animal cell — schematic, not to scale. Not every cell contains every structure.

What it does

Section titled “What it does”
  • Digestion — breaks down worn-out organelles, debris, and large molecules into reusable parts.
  • Defense — destroys bacteria and other particles the cell has engulfed.
  • Recycling — returns the salvaged building blocks to the cytoplasm for reuse.

Key idea

Section titled “Key idea”

Lysosomes keep the cell clean and self-renewing. Their enzymes are safely contained, because releasing them freely would digest the cell itself. Inherited faults in these enzymes cause “lysosomal storage diseases.”