Which hypothesis helps to explain why all organisms share the same genetic code?

• A. The Independent Evolution Hypothesis
• B. The Genetic Drift Hypothesis
• C. The Symbiotic Origin Hypothesis
• D. The Universal Ancestor Hypothesis

Answer: (D)

Verified step by step guidance

1. Understand the concept of the genetic code: The genetic code is a set of rules by which information encoded in genetic material (DNA or RNA sequences) is translated into proteins by living cells. It is nearly universal across all known organisms.
2. Explore the Universal Ancestor Hypothesis: This hypothesis suggests that all life forms on Earth share a common ancestor. This common ancestor had a genetic code that has been passed down and conserved through evolution.
3. Consider the implications of a universal genetic code: If all organisms share the same genetic code, it implies that this code was established early in the history of life and has been maintained due to its efficiency and effectiveness in protein synthesis.
4. Compare with other hypotheses: The Independent Evolution Hypothesis would suggest different genetic codes could evolve independently, which is not supported by the universal nature of the genetic code. The Genetic Drift Hypothesis involves random changes in allele frequencies, not the establishment of a universal code. The Symbiotic Origin Hypothesis relates to the origin of eukaryotic cells, not the genetic code.
5. Conclude why the Universal Ancestor Hypothesis is favored: The widespread conservation of the genetic code across diverse life forms supports the idea of a single ancestral origin, making the Universal Ancestor Hypothesis the most plausible explanation for the shared genetic code.