lysosome

American  

[lahy-suh-sohm] / ˈlaɪ səˌsoʊm /

noun

Cell Biology.

1. a cell organelle containing enzymes that digest particles and that disintegrate the cell after its death.

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lysosome British  

/ ˈlaɪsəˌsəʊm /

noun

1. any of numerous small particles, containing digestive enzymes, that are present in the cytoplasm of most cells

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lysosome Scientific  

/ lī′sə-sōm′ /

1. A cell organelle that is surrounded by a membrane, has an acidic interior, and contains hydrolytic enzymes that break down food molecules, especially proteins and other complex molecules. Lysosomes fuse with vacuoles to digest their contents. The digested material is then transported across the organelle's membrane for use in or transport out of the cell.

2. See more at cell

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Other Word Forms

• lysosomal adjective

Etymology

Origin of lysosome

First recorded in 1950–55; lyso- + -some ³

Explanation

In biology, a lysosome is an organelle that contains digestive enzymes and is wrapped in a membrane. Lysosomes act as a sort of digestive system for cells. The job of a lysosome is to get rid of cell parts that are old or unneeded — basically, to break down and clear away any waste products. If the cell itself is too damaged to function properly, a lysosome can also help to break down the entire cell, a process called "programmed cell death." The word lysosome was coined in 1955, from roots meaning "loosening" and "the body," to give a sense of their digestive properties.

Example Sentences

Both approaches successfully improved lysosome function, boosted the removal of progerin, and reduced signs of cellular aging, such as DNA damage, growth arrest, and loss of cell vitality.

From Science Daily • Nov. 7, 2025

The results showed a significant reduction in the activity of genes linked to lysosome function.

From Science Daily • Nov. 7, 2025

Another key protein, progranulin, regulates cell growth and a part of the cell called the lysosome that breaks down cellular waste products.

From Salon • Feb. 26, 2023

At the tip of the head of a sperm cell is a structure like a lysosome called the acrosome, which contains enzymes.

From Textbooks • Apr. 25, 2013

After phagocytosis by a macrophage, the phagocytic vesicle fuses with an intracellular lysosome.

From Textbooks • Apr. 25, 2013