Structure and Function of RNA

Introduction

• Topic: Structure of RNA and its function
• RNA is a type of polymer made up of monomers called nucleotides.

Structure of RNA

• Nucleotide Components:
  • Ribose Sugar: A pentose sugar with 5 carbons.
    • Key identifier for RNA (R in RNA stands for Ribose).
  • Nitrogenous Bases: Adenine (A), Guanine (G), Cytosine (C), Uracil (U).
    • Differences from DNA: RNA contains Uracil instead of Thymine.
  • Phosphate Group: A single phosphate group similar to DNA.

Differences Between RNA and DNA

• Sugar Component:
  • RNA: Contains ribose.
  • DNA: Contains deoxyribose.
• Strand Structure:
  • RNA: Single stranded.
  • DNA: Double stranded.
• Nitrogenous Bases:
  • RNA: Contains Uracil.
  • DNA: Contains Thymine.
• Length:
  • RNA: Shorter, single gene copies.
  • DNA: Longer, contains entire genome.

Function of RNA

• General Function: Copying and transferring genetic information.
• Types of RNA:
  1. mRNA (Messenger RNA):
     • Copies a single gene from DNA (shorter than DNA).
     • Moves from nucleus to ribosome to aid in protein synthesis.
     • Short-lived due to exposure to enzymes outside the nucleus.
     • Single stranded with codons (three bases) coding for amino acids.
  2. tRNA (Transfer RNA):
     • Found in the cytoplasm.
     • Single stranded but folds into a cloverleaf shape (held by hydrogen bonds).
     • Transfers amino acids to mRNA on ribosomes.
     • Contains anticodon which pairs with mRNA codon for specific amino acids.
  3. rRNA (Ribosomal RNA):
     • Combines with proteins to form ribosomes.

Comparing RNA to DNA

• Differences in Monomers:
  • RNA: Contains Uracil, ribose.
  • DNA: Contains Thymine, deoxyribose.
• Differences in Polymers:
  • RNA: Shorter, single gene copies, single stranded.
  • DNA: Longer, full genome, double stranded.

Conclusion

• Understanding the structure and function of RNA helps in comprehending its role in genetic information transfer and protein synthesis.