Lecture Notes on DNA and RNA

Introduction

• DNA often receives recognition for its structure and role in genetics.
• RNA is equally important, serving as the messenger that allows cells to produce proteins.
• RNA World Hypothesis suggests RNA may have existed before DNA.

DNA vs. RNA

Location

• DNA: Found in the nucleus of eukaryotic cells.
• RNA: Found both inside and outside the nucleus in eukaryotic cells; no nucleus in prokaryotic cells.

Structure

• Both are nucleic acids, biomolecules with nucleotides as monomers.
• Nucleotide Components: Phosphate, sugar, base.
• DNA: Double-stranded, anti-parallel strands, sugar is deoxyribose.
• RNA: Single-stranded, sugar is ribose.

Bases

• DNA Bases: Adenine (A), Thymine (T), Guanine (G), Cytosine (C).
  • Mnemonic: A-T (Apples in the tree), C-G (Car in the garage).
• RNA Bases: Adenine (A), Uracil (U), Guanine (G), Cytosine (C).
  • Mnemonic: A-U (Apples under), C-G (Car in the garage).

Role of RNA in Protein Synthesis

• mRNA (Messenger RNA): Carries DNA message to ribosomes.
• rRNA (Ribosomal RNA): Major component of ribosomes.
• tRNA (Transfer RNA): Matches amino acids to mRNA codons.

Protein Synthesis

• mRNA leaves nucleus to ribosome.
• Codon charts show amino acids matching mRNA codons.
• Amino acids form polypeptide chains, which compose proteins.

Quick Quiz Questions

1. Question: If I have 8 DNA nucleotides, how many DNA bases and base pairs?
   • Answer: 8 bases, 4 base pairs.
2. Question: Complementary DNA strand for bases ATTGAC?
   • Answer: T-A-A-C-T-G using base pairing rules.
3. Question: Complementary RNA bases for DNA strand ATTGAC?
   • Answer: U-A-A-C-U-G using RNA base pairing rules.

Final Thoughts

• Models don't fully capture 3D structure and other details.
• Encouragement to explore further resources for deeper understanding.

Conclusion

• Stay curious and keep exploring the intricate details of DNA and RNA.