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6EZpZ TIL that the digestive system is an "open" system because the mouth and the anus open to the outside of the body. Food technically is passing through us on the outside...
XE8dQ TIL that normal matter only makes up 5 percent of the total Universe
7r7Zx TIL: Microorganisms constitute more than 90% of the biomass in the sea. It is estimated that viruses kill approximately 20% of this biomass each day, and that there are 15 times as many viruses in the oceans as there are bacteria and archaea