Lysosomes vs Peroxisomes
Lysosomes and peroxisomes are enzyme containing single membranous organelles found in eukaryotic cells. They differ in many ways including their enzymes, size and the amount they present in a single cell.
What is Lysosome?
Lysosome is a single membrane organelle found in eukaryotic cells. Moreover, lysosomes are found in almost all the animal cells except red blood cells, and all the eukaryotic plant cells and fungi. These organelles are round-shaped, dense sacs, which mainly contain lytic enzymes. Lysosomes have a size of about 0.23 to 0.5 µm in the diameter range and are considered as ultramicroscopic organelles.
The lytic enzymes including ribonuclease, deoxyribonuclease, phosphatases, cathepsin, lysozyme, sulphatases, and glycosidases are stored in central vacuole of lysosome, which is surrounded by a dense granulated stroma. These enzymes are commonly called acid hydrolases because they activate at acidic pH, which is lower than pH 7.
It is assumed that lysosomes are formed either from vesicles of Golgi apparatus or endoplasmic reticulum. In a cell, four types of lysosomes can be found, namely; primary lysosome, secondary lysosome, tertiary lysosome, and autophagic vacuoles. The main roles of lysosomes are mobilization of food from the storage organs when starving, contribution of intracellular digestion, digestion of embryonic organs during metamorphosis (ex: digestion of the tail in dipole), removing old organelles and cells, and controlling the secretion processes of endocrine glands.
What is Peroxisome?
Peroxisomes are membrane bounded microbodies that contain several oxidative enzymes. Moreover, they are oval shaped organelles with dense homogenous stroma. The main role of the peroxisomes is to produce and decompose hydrogen peroxide during the detoxifying of certain molecules.
Usually there can be seventy to hundred peroxisomes in a single cell, and they are in the range of 0.5-1.0 µm in diameter. The lifespan of a peroxisome is about 4-5 days. The enzymes including catalase, urate oxidase, D-amino oxidase and α-hydroxylic acid oxidase are synthesized in ribosomes of rough endoplasmic reticulum. The oxidative enzymes of peroxisomes use oxygen to remove hydrogen molecules, thus helps to detoxify certain organic molecules like alcohol. This reaction produces hydrogen peroxide, which is eventually degraded by the catalase enzyme in peroxisome.
What is the differences between Lysosome and Peroxisome?
• Lysosomes contain hydrolytic enzymes, whereas peroxisomes contain oxidative enzymes.
• Peroxisomes are usually larger than lysosomes.
• In a single cell, there are 70-100 peroxisomes and 15-20 lysosomes present.
• Peroxisomes are derived from endoplasmic reticulum (ER), whereas lysosomes are believed to be evolved from either Golgi apparatus or ER.
• Lysosomes contribute to digest cells and organelles, whereas peroxisomes help to digest toxic molecules in cells.
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