This is part of the ribosome, the machine in all living things that 3D prints proteins to order, based on digital instructions in our DNA. All of life consists of proteins or things built by proteins. In our labs we can barely imitate the ribosome somewhat using cumbersome pieces of fragile equipment that need lots of expert handling. The ribosome meanwhile can print copies of itself and is 20nm large. Bow before its glory.
https://www.genome.gov/genetics-glossary/Ribosome
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