Other contributors have said "What do you call the part of an atom that contains protons and neutron?" is the same question as "Which part of an atom has neutrons and protons?" If you believe that these are not asking the same thing and should be answered differently, click here
Protons and neutrons are found in the nucleus of an atom. These subatomic particles "bond" together during fusion to create the nucleus. WHO THEY HELLS KNOWS.