What carries the complement of a DNA sequence from the nucleus to the ribosomes for protein synthesis?

What carries the complement of a DNA sequence from the nucleus to the ribosomes for protein synthesis?

• A. mRNA
• B. tRNA
• C. rRNA
• D. snRNA

Answer: (A)

The main idea is that the genetic message needs to be carried from the DNA in the nucleus to the ribosome where proteins are built. This role is fulfilled by messenger RNA. During transcription, an RNA copy is made that is complementary to the DNA template strand and resembles the DNA coding strand with uracil replacing thymine. This mRNA exits the nucleus and provides the sequence that ribosomes read to assemble amino acids into a protein. Other RNA types have different jobs: transfer RNA ferry’s amino acids to the ribosome and matches its anticodon to the mRNA codon, ribosomal RNA is a structural and catalytic part of the ribosome itself, and small nuclear RNA participates in splicing pre-mRNA in the nucleus. Thus, only mRNA serves as the information carrier from DNA to the ribosome for protein synthesis.

The main idea is that the genetic message needs to be carried from the DNA in the nucleus to the ribosome where proteins are built. This role is fulfilled by messenger RNA. During transcription, an RNA copy is made that is complementary to the DNA template strand and resembles the DNA coding strand with uracil replacing thymine. This mRNA exits the nucleus and provides the sequence that ribosomes read to assemble amino acids into a protein.

Other RNA types have different jobs: transfer RNA ferry’s amino acids to the ribosome and matches its anticodon to the mRNA codon, ribosomal RNA is a structural and catalytic part of the ribosome itself, and small nuclear RNA participates in splicing pre-mRNA in the nucleus. Thus, only mRNA serves as the information carrier from DNA to the ribosome for protein synthesis.