Practice question

Question

E. coli is grown exclusively in a medium containing ¹⁵ NH ₄ Cl as the sole nitrogen source. Subsequently, the cells were shifted to a medium containing ¹⁴ NH ₄ Cl. The molar ratio of hybrid DNA ( ¹⁵ N ¹⁴ N) to light DNA ( ¹⁴ N ¹⁴ N) after four generations (rounded off to two decimal places) will be _____ . (NAT)