Suppose many of the atoms of nitrogen in a double-stranded molecule of DNA, of isotope N-14, were replaced with the isotope N-15. What afffect would this have?
a) The nitrogeneous bases would become slightly basic.
b) the Base pairing would no longer occur naturally,
c) The DNA could turn into RNA
d) there would be no detectable effect on the DNA
f) The molecule would increase in mass slightly.