DNA vs RNA and 3 Types of RNA

RNA vs. DNA

Overview

• DNA (Deoxyribonucleic Acid)

  • Double-stranded

  • Contains deoxyribose sugar

  • Thymine as one of the nucleobases

• RNA (Ribonucleic Acid)

  • Usually single-stranded

  • Contains ribose sugar

  • Uracil replaces thymine in RNA

Structural Differences

Sugar and Phosphate Backbone

• DNA:

  • Deoxyribose sugar

  • Phosphate group

• RNA:

  • Ribose sugar

  • Phosphate group

Nucleobases

• DNA:

  • Adenine (A)

  • Cytosine (C)

  • Guanine (G)

  • Thymine (T)

• RNA:

  • Adenine (A)

  • Cytosine (C)

  • Guanine (G)

  • Uracil (U)

Types of RNA

1. mRNA (Messenger RNA)

• Function:

  • Initiates protein synthesis by carrying genetic information from DNA to the cytoplasm.

• Mechanism:

  • mRNA copies genetic instructions and exits the nucleus to attach to a ribosome.

2. tRNA (Transfer RNA)

• Function:

  • Delivers amino acids to ribosomes for protein synthesis.

• Structure:

  • One end attaches to a specific amino acid; the other end (anticodon) matches with mRNA codon.

3. rRNA (Ribosomal RNA)

• Description:

  • Found in ribosomes, which are the sites of protein synthesis.

• Function:

  • Comprises 60% of ribosome structure and plays a catalytic role in forming peptide bonds between amino acids.