Structure of RNA

• What is mRNA?

  Messenger RNA.
• When is mRNA synthesised

  During transcription.
• What is the role of mRNA?

  To carry genetic information from DNA in the nucleus to the ribosomes in the cytoplasm.
• Why does mRNA have to be small?

  To be able to leave the nucleus.
• What does the genetic code in mRNA determine?

  The sequence of amino acids in the protein.
• What is a codon? 


  A sequence of 3 bases that code for a specific amino acid.
• What is RNA?


  A single-stranded polymer made of repeating mononucleotides.
• What is in each RNA nucleotide?

  A ribose sugar, a phosphate group, and an organic base.
• What does RNA stand for?


  Ribonucleic acid.
• What organic bases are in RNA?

  Adenine, guanine, cytosine, and uracil.
• What are the features of mRNA?

  It's a small, single-stranded, linear molecule with a base sequence complementary to a DNA sequence, and it has codons.
• What are the base sequences of mRNA determined by?

  The sequence of bases on the DNA.
• What happens to mRNA once it is formed?

  It leaves the nucleus via nuclear pores and enters the cytoplasm where it associates with ribosomes.
• What does mRNA act as when it associates with the ribosomes?

  A template for protein synthesis.
• What do the sequences of codons determine?

  The amino acid sequence of a specific polypeptide.
• What is tRNA?


  Transfer RNA.
• What are the features of tRNA?

  It's a small, single-stranded, clover-leaf-shaped molecule with hydrogen bonds between complementary base pairs, an anticodon, and an amino acid binding site.
• What shape is tRNA folded into?

  A clover-leaf shape.
• What is each tRNA molecule specific to?

  An amino acid.
• What is the anticodon on tRNA?


  A specific sequence of 3 bases on the end of tRNA that are complementary to a codon on mRNA.
• How does RNA join with DNA?

  By complementary base pairings.
• What does an anticodon pair with?


  Three complementary bases that make up a codon on mRNA.
• How is tRNA structurally suited for its role?

  It has an anticodon for complementary base pairing with a codon of mRNA, and it has an end chain for attaching amino acids.