Electrons are elementary particles, which means they are not composed of smaller constituents. On the other hand, protons and neutrons are composite particles made up of quarks.
The fundamental building blocks of matter, as described by the Standard Model of particle physics, are quarks and leptons. Quarks are elementary particles that have a property called color charge, and they interact through the strong nuclear force. Leptons, such as electrons, do not possess color charge and do not participate in the strong nuclear force.
Protons and neutrons, which are baryons, are composed of three quarks each. Protons consist of two up quarks and one down quark, while neutrons consist of one up quark and two down quarks. The combination of these quarks within the baryons gives rise to their properties, such as their electric charge and mass.
Electrons, on the other hand, belong to the lepton family and are not composed of quarks. They are fundamental particles with a negative electric charge and a significantly smaller mass compared to quarks. Electrons interact through the electromagnetic force and the weak nuclear force.
The distinction between quarks and leptons is a fundamental aspect of the Standard Model, which categorizes particles based on their properties and interactions. While protons and neutrons are indeed composed of quarks, electrons are elementary particles and do not have a composite structure.