mRNA's Nucleotide Structure

Steps:

• Recall mRNA is single-stranded RNA transcribed from DNA, carrying genetic code to ribosomes.
• Evaluate option A: In eukaryotes, processing removes introns (non-coding), not exons (coding).
• Evaluate option B: mRNA uses adenine and guanine (same purines as DNA) but uracil instead of thymine.
• Evaluate option C: mRNA nucleotides include ribose sugar linked to phosphate via phosphodiester bonds, matching RNA structure.
• Evaluate option D: mRNA uses ribose, not deoxyribose (which is in DNA).

Why C is correct:

• RNA, including mRNA, consists of ribonucleotides with ribose sugar and phosphate forming the backbone through phosphodiester bonds, as defined in molecular biology.

Why the others are wrong:

• A: Eukaryotic mRNA processing retains exons and splices out introns from pre-mRNA.
• B: mRNA shares DNA's purines (A, G); it substitutes uracil (pyrimidine) for thymine.
• D: mRNA monomers contain ribose sugar, not deoxyribose found in DNA.

Final answer: C