Which base replaces thymine (T) in base sequence of messenger RNA (mRNA)?

Explanation

Messenger RNA (mRNA) is a type of RNA that carries genetic information from DNA to ribosomes, which are the sites of protein synthesis. mRNA is made up of four different nucleotide bases: adenine (A), cytosine (C), guanine (G), and uracil (U). In DNA, thymine (T) is the base that pairs with adenine (A). However, in mRNA, uracil (U) pairs with adenine (A) instead of thymine (T). So, the correct answer to this question is Option D: Uracil (U). Uracil is the base that replaces thymine (T) in the base sequence of mRNA. It is important to note that this is specific to mRNA and not DNA. DNA still follows the base pairing rules of A with T and G with C. Understanding the different types of RNA and their functions is important in biology because it is necessary for protein synthesis. For more information on this topic, please refer to your recommended textbooks.