Question

Write important structural and functional differences between DNA and RNA.

Hint:

Remember, DNA is stable and stores genetic information, while RNA is involved in protein synthesis and is more transient in nature.

Answer 1

DNA (Deoxyribonucleic Acid) and RNA (Ribonucleic Acid) are both nucleic acids but differ in their structural and functional characteristics. Below are the key differences:
Structural Differences:
1. Sugar Molecule:}
- DNA contains deoxyribose sugar, which lacks one oxygen atom (at the 2' carbon) compared to ribose.
- RNA contains ribose sugar, which has a hydroxyl group (-OH) attached to the 2' carbon atom.
2. Strand Type:}
- DNA is typically double-stranded, forming a double helix structure.
- RNA is usually single-stranded and can form various structures like hairpins.
3. Nitrogenous Bases:}
- DNA contains the bases adenine (A), thymine (T), cytosine (C), and guanine (G).
- RNA contains the bases adenine (A), uracil (U), cytosine (C), and guanine (G). Note that RNA uses uracil instead of thymine.
4. Helical Structure:}
- DNA has a right-handed double helix structure.
- RNA is single-stranded and may adopt various secondary structures.
5. Length and Stability:}
- DNA is generally longer and more stable than RNA, designed to store genetic information.
- RNA is usually shorter and less stable, designed for transient functions in the cell.
Functional Differences:
1. Genetic Material:}
- DNA carries the genetic blueprint for the synthesis of proteins and is involved in the storage and transmission of genetic information.
- RNA plays a role in transcribing the genetic code from DNA and is involved in the synthesis of proteins (as mRNA, rRNA, and tRNA).
2. Types of RNA:}
- DNA does not have different types but is used in the formation of mRNA, rRNA, and tRNA in RNA transcription.
- RNA has several types: mRNA (messenger RNA), rRNA (ribosomal RNA), and tRNA (transfer RNA), each playing a role in protein synthesis.
3. Replication and Transcription:}
- DNA is self-replicating, meaning it can duplicate itself during cell division.
- RNA is transcribed from DNA and is not capable of replication itself but can be synthesized through transcription.
4. Function in Protein Synthesis:}
- DNA stores the instructions for protein synthesis, while RNA is involved in the direct synthesis of proteins in the cytoplasm.