DNA vs RNA: Lecture Notes

Introduction

• DNA often gets more attention due to its double helix structure and role in storing genetic information.
• RNA is equally important for transferring genetic messages to cells for protein production.
• RNA World Hypothesis: RNA may have existed before DNA.

Locations in Cells

• Eukaryotic Cells:
  • DNA is found in the nucleus.
  • RNA is found both inside and outside the nucleus.
• Prokaryotic Cells:
  • Lack a nucleus.

Structure and Components

• Both DNA and RNA are nucleic acids, a type of biomolecule.
• Nucleotides are the monomers:
  • Each nucleotide has three parts: phosphate, sugar, and a base.

DNA vs RNA

• DNA:
  • Generally double-stranded, with strands running anti-parallel.
  • Sugar: Deoxyribose.
  • Bases: Adenine (A), Thymine (T), Guanine (G), Cytosine (C).
  • Base pairing: A-T, C-G (mnemonics: Apples in the tree, Car in the garage).
• RNA:
  • Generally single-stranded.
  • Sugar: Ribose.
  • Bases: Adenine (A), Uracil (U), Guanine (G), Cytosine (C).
  • Base pairing: A-U (mnemonics: Apples under), C-G stays the same.

Roles of RNA in Protein Synthesis

• mRNA (Messenger RNA):
  • Carries genetic message from DNA to ribosomes.
  • Can exit the nucleus.
• rRNA (Ribosomal RNA):
  • Major component of ribosomes.
• tRNA (Transfer RNA):
  • Transfers amino acids to match mRNA codons.
  • Codon charts help determine which amino acid corresponds to each mRNA codon.

Protein Synthesis Process

• Amino acids join to form polypeptide chains.
• Proteins consist of one or more polypeptide chains.
• Proteins play various crucial roles in the body.

Quiz Questions

1. DNA Nucleotides and Bases:
   • 8 DNA nucleotides have 8 bases, forming 4 base pairs.
2. Complementary DNA Strand Bases:
   • Given: ATTGAC, Complement: TAACGT.
3. Transcription to RNA Bases:
   • Uses RNA bases with uracil instead of thymine.
   • Complement: replaces thymine with uracil.

Conclusion

• Models lack the 3D shape detail; further readings are encouraged.
• Stay curious and explore more about DNA and RNA.

Note: Lecture encourages further exploration into the structure of DNA/RNA and protein synthesis.

Further Reading:

• Links provided in lecture for additional exploration.