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Peroxisomes are cell organelles that are found in both plant and animal cells.  This cell organelle does a similar job as the mitochondria organelle. However, it only has a single-wall membrane which holds all it together.

Cartoon illustration of animal cell with peroxisomes

The peroxisome organelle looks like the lysosome organelle under a microscope. There are many peroxisome organelles within a cell and they are responsible for many jobs. Their main job is to transform nutrients into energy!

What Does A Peroxisome Do?

Image of a peroxisome eating a fatty acid

Peroxisomes break down fatty acids into simple molecules

Peroxisomes take nutrients that the cell has collected and breaks them down into usable energy.  The most common nutrient a peroxisome transforms into energy is a “fatty acid”.  In animal cells, the peroxisome organelles and mitochondria work together to turn these fatty acids into energy.  Whereas in plant cells, the fatty acids are broken down only by the peroxisome organelles.

Transforming these fatty acids into energy is a two-step process.  Firstly, the peroxisome breaks down the fatty acid into a chemical known as hydrogen peroxide.  Hydrogen peroxide is a toxic chemical to the cell so the peroxisome must perform its second step.  The second step is to break down the hydrogen peroxide into water and oxygen which the cell uses for other jobs.  In both of these steps, energy is created for the animal or plant to use.

Number of Peroxisomes in a Cell

The number of peroxisomes in a cell varies from cell to cell.  You will find lots of them in organs which help in digestion and help detoxify our bodies.  But, you won’t find many them in cells that don’t have a role in digestion.  For example, you will find lots of peroxisomes in our liver and kidney cells.  However, you won’t find many in our red blood cells.

Other Facts About Peroxisome

Peroxisomes are one of the cell organelles that grow all the time.  When a peroxisome gets big enough, it will split into two smaller peroxisomes.  Another interesting fact is that they got their weird name because they create hydrogen peroxide. This can be helpful in remembering what a peroxisome does.

Peroxisomes exist in many places within an organism to provide energy for different things.  In seed cells in a plant, peroxisomes create energy for the cell to grow.  In leaf cells, peroxisomes create energy to help with photosynthesis.


Written by: Daniel Gabioud