LIFE SCIENCE

Detailed explanation-1: -Uracil (U) is one of the four nucleotide bases in RNA, with the other three being adenine (A), cytosine (C) and guanine (G). In RNA, uracil pairs with adenine. In a DNA molecule, the nucleotide thymine (T) is used in place of uracil.

Detailed explanation-2: -Uracil is the nitrogenous base present only in RNA, but not in DNA. Thymine is in DNA. DNA have thymine, guanine, adenine and cytosine. Thymine is replaced by uracil in RNA.

Detailed explanation-3: -Because thymine has a higher resistance to photochemical mutation and makes the genetic code more durable, DNA uses it instead of uracil. This is required to store all the data required for life to function.

Detailed explanation-4: -In RNA, uracil replaces thymine. Uracil binds to adenine via two hydrogen bonds. In DNA, the uracil is replaced by thymine. Uracil is a dimethylated form of thymine.