Lysosomes

• When are lysosomes formed?

  When the vesicles produced by the Golgi contain enzymes such as proteases and lipases.
• What other enzyme do vesicles contain?

  Lysozymes.
• What are lysozymes?


  Enzymes that hydrolyse the cell walls of certain bacteria.
• How many enzymes may a lysosome contain?

  50
• What size are lysosomes?

  Up to 1.0 micrometres in diameter.
• What do lysosomes do with the enzymes?

  Isolate them from the rest of the cell before releasing them to the outside or into a phagocytic vesicle within the cell.
• What are the functions of lysosomes?

  Hydrolyse material ingested by phagocytic cells (WBC and bacteria), releases enzymes into the outside of the cell, digests worn-out organelles, and breaks down cells completely after they have died.
• What is the outside of the cell called?

  Exocytosis.
• Why do lysosomes release enzymes into the exocytosis?

  To destroy material around the cell.
• Why do lysosomes digest worn-out organelles?

  So the useful chemicals they are made of can be re-used.
• What is the process of lysosomes breaking down cells after they have died called?

  Autolysis.
• Where are lysosomes abundant in?

  Secretory cells like epithelial and phagocytic cells.
• What do lysosomes hydrolyse?

  Material ingested by phagocytic cells.
• What do lysosomes release and where?

  Enzymes into the outside of a cell.
• What do lysosomes digest?

  Worn-out organelles.
• What do lysosomes break down?

  Cells after they have died.