Lysosomes - Structure And Function

All living things are made up of cells. A cell is the fundamental and functional unit of every living organism.  But non-living things lack cells and thus, they are stationary.  Living organisms can either be a unicellular or a multicellular organism, depending on the number of cells they are made of. Whether unicellular or multicellular organisms, they all consist of the same cell organelles. They have specific functions and make the cell alive and self-sufficient. Lysosomes are one the cell organelle which has a crucial role to play. Let’s learn more about lysosomes, their structure, and function.


Based on the cell structure and types of cell organelles present, living organisms have been classified into two categories, prokaryotes, and eukaryotes. Eukaryotes are multicellular organisms. Prokaryotes are generally unicellular organisms; however, few multicellular organisms are prokaryotes. A prokaryotic cell does not contain well-defined membrane-bound organelles.  Most of the organelles which a eukaryotic cell contains are absent in a prokaryotic cell.  The lysosome is one among them.

Lysosomes are small membrane-bound sac-like structures which release digestive enzymes that break down food. They act as a waste bin of the cell and keep the cell clean. Lysosomes are present in eukaryotic cells but a prokaryotic cell lacks them.  When a foreign matter enters the cell, they release their enzymes which break the foreign substance into tiny pieces and kill them. They also remove the old and damaged or dead organelles from the cell and thus, protect the cell from further damages and consequences.  Lysosomes are also responsible for the digestion of food which we eat. They release an enzyme which is powerful enough to break any organic matter.  Rough endoplasmic reticulum (RER) in the cell is responsible for the synthesis of these enzymes.


A damaged or infected cell fails to do its functions due to metabolic irregularities or other reasons. In such situations, the lysosomes inside a cell burst out and engulf their own cell. Thus, it protects the other cells of the body from further infections and damages. Since lysosomes engulf their own cell, they are known as “suicide bags” of a cell. Hence, it has a great role in immunity of the body.

To know more about lysosomes and other cell organelles visit Byju’s.

Practise This Question

DIRECTIONS: The following questions have four choices (a), (b), (c) and (d) out of which only one is correct. You have to choose the correct alternative.

Lipids and proteins constituting the cell membrane are synthesized at: