What would happen to a nucleus without the presence of neutrons?

Neutron is a subatomic particle composed of elementary particle called quarks(1 up quark and 2 down quarks).in beta emission,In ?? decay, the weak interaction converts a neutron (n) into a proton (p) while emitting an electron (e?) and an electron antineutrino (?e).                                                i think if there were no neutrons ,isotopes would not have been formed....................The neutron plays an important role in many nuclear reactions. For example, neutron capture often results in neutron activation, inducing radioactivity. In particular, knowledge of neutrons and their behavior has been important in the development of nuclear reactors and nuclear weapons. The fissioning of elements like uranium-235 and plutonium-239 is caused by their absorption of neutrons.

Another use of neutron emitters is the detection of light nuclei, particularly the hydrogen found in water molecules. When a fast neutron collides with a light nucleus, it loses a large fraction of its energy. By measuring the rate at which slow neutrons return to the probe after reflecting off of hydrogen nuclei, a neutron probe may determine the water content in soil.