<span>it comes and goes through the madreporite - a small valve like structure</span>
This would be enzymes made of proteins.
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It suggests that the bone will have equal strength in all directions.
Answer:
The Miller–Urey experiment (or Miller experiment) was a chemical experiment that simulated the conditions thought at the time to be present on the early Earth, and tested the chemical origin of life under those conditions. The experiment supported Alexander Oparin's and J. B. S.
Explanation: