Quarks are thought to be the building blocks of protons. Which was most affected by the discovery of the quark?

Discovering quarks showed that protons are made of smaller particles, so protons are not the most fundamental building blocks. This most directly changed the view that matter could not be broken down further than protons. The discovery did not change the proton’s measured +1 charge or the basic model of a nucleus containing protons and neutrons.

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