Properties of Genetic Material (DNA vs RNA)
- A genetic material must have the following properties:
- Ability to generate its replica (Replication).
- Chemical and structural stability.
- Provide the mutations that are required for evolution.
- Ability to express as Mendelian Characters.
- Comparison of DNA and RNA stability and reactivity:
- DNA: Double stranded → RNA: Single stranded.
- DNA: Presence of thymine → RNA: Presence of Uracil.
- DNA: Absence of 2’-OH in sugar → RNA: Presence of 2’-OH in sugar.
- RNA is unstable. So, RNA viruses (e.g., Q.B bacteriophage, Tobacco Mosaic Virus, etc.) mutate and evolve faster.
- DNA strands are complementary. On heating, they separate. In appropriate conditions, they come together. In Griffith’s experiment, some properties of DNA of the heat-killed bacteria were not destroyed. It indicates the stability of DNA.
- For the storage of genetic information, DNA is better due to its stability. But for the transmission of genetic information, RNA is better.
- RNA can directly code for protein synthesis, hence can easily express the characters. DNA is dependent on RNA for protein synthesis.
RNA World
- RNA was the first genetic material.
- It acts as genetic material and catalyst.
- Essential life processes (metabolism, translation, splicing, etc.) evolved around RNA.
- DNA evolved from RNA for stability.
Select a Topic 👇
-
Topic 1: The DNA
Topic 2: The Search for Genetic Material
Topic 3: Properties of Genetic Material, RNA World
Topic 4: DNA Replication
Topic 5: Transcription
Topic 6: Genetic Code, Types of RNA
Topic 7: Translation (Protein Synthesis)
Topic 8: Regulation of Gene Expression, Operon Concept
Topic 9: Human Genome Project (HGP)
Topic 10: DNA Fingerprinting