Final answer:
The building blocks of the universe are called fundamental particles. These particles are the smallest known constituents of matter and cannot be broken down into anything simpler.
Step-by-step explanation:
The building blocks of the universe are called fundamental particles. These particles are the smallest known constituents of matter and cannot be broken down into anything simpler. They include particles such as quarks, which are the building blocks of protons and neutrons, and electrons, which orbit the nucleus of an atom.
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