Is Neutron to Proton Transformation Possible in Nuclear Reactions?

[semc]

I remembered my teacher once said that a proton can be a neutron or the other way round but i am not too sure about it so my friend propose that neutron --> proton + electron. i am not too sure about this so can anyone tell me if this is true.

If this is true, i calculate that the mass defect is extremely small and the energy is power raised to about negative 7 or 8. I thought that the force that holds the electrons and protons within an atom is one of the four fundamental forces? Is it possible that the force is that small in magnitude

Thanks

 

[neutrino]

Did your teacher mention anything about beta decay?
http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/beta.html#c2

 

[semc]

Not very sure but i think he mention something about 'some reaction' in the nucleus and cause the change??