Chapter 2.2.6: Lysosomes

First I think it is important to understand how scientists "see" small
cellular organelles. One way they see these organelles is through staining,
when you stain a organelle or a cell, you will see different characteristics
based on the stain. Another way to 'see' what is there is by separating
the cell by the size and weight of the organelles (through centrification,
basically spinning the contents of the cell around VERY fast in a substance
that allows different layers of 'stuff' depending on its density).

The lysosome is about the same, the lysosome tends to stain
more granular than the peroxisome. A peroxisome will
often have a crystalline structure inside. (like a crystalline
shape inside a sphere).

Lysosomes

The structures vary in size from 0.2 to 2 micrometers in diameter.
The staining reveals a crystal like matrix in spherical vesicles.
The crystalloid matrix is urate oxidase.
These are small organelles containing around 40 enzymes for intercellular
digestion. The lysosome membrane helps to protect the enzymes as much
as it helps protect the cell. This is because the optimal pH for these
enzymes is around a pH of 5. The membrane of the lysosome is again a
lipid bilayer and is thought to have a ATP hydrolysis to pump H+ into
the lysosome to maintain the pH. This also has another affect, that is
free protons. Other small molecules can pass through the lysosome membrane,
but will then become charged by picking up a free proton, then they are
less likely to be able to leave the lysososome.

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Please send questions/comments/suggestions to: Mark Dalton at markwdalton@gmail.com.