Diatoms Trap CO2 in their bodies and release oxygen into the atmosphere

Then they fall when they die to the bottom of the ocean and become a part of the sea floor around the world thus trapping the CO2 there on the ocean bed worldwide. By doing this they reduce ongoing the amount of CO2 in the Atmosphere  for thousands and millions of years so far since they came into existence in oceans around the world. Diatoms are very small. The biggest diatoms are the width of a human hair.

Nearly all diatoms are microscopic - cells range in sizefrom 2 µm to 500 µm (= 0.5 mm). The biggest diatoms are about the width of a human hair. Scientists use light microscopes (LM) or scanning electron microscopes (SEM) to view diatom.

What are Diatoms? - Diatoms of North America

https://diatoms.org/what-are-diatoms

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