Construct a chart to demonstrate the molecular features of the primary domains of life. Why are there overlapping or shared molecular features between all three domains?

Question

Relate the shared and unique molecular features of each domain to early evolution, the last universal common ancestor (LUCA), and the evolution of the three domains
What will be an ideal response?

Answer 1

Answer: Answers should include some of the information shown in Figure 12.10, Figure 12.13, and Table 12.1 in the textbook. The molecular features shared by all three domains of life, such as genomes of dsDNA, RNA as genetic messenger, RNA as a catalyst, and ribosomes catalyzing protein synthesis, were all feature found in the last universal common ancestor. These properties of life are thought to have evolved in the pre-cellular and early cellular stages of evolution. Features that are shared between Bacteria and Archaea or between Archaea and Eukarya, demonstrate when these feature evolved and illustrate how Archaea are more similar to Eukarya. The larger number of shared molecular characteristics between Archaea and Eukarya (such as introns, histones, multiple chromosomal origins, helicase and DNA polymerase similarity, TATA promoters, RNA polymerase similarity, and elongation factor similarity) support the hypothesis that Archaea gave rise to Eukarya through endosymbiosis of a bacterial cell to form mitochondria or chloroplasts inside of a larger archaeal cell. Bacteria and Eukarya do not share any unique characteristics that are not also shared with Archaea, which also supports the hypothesis that Eukarya were derived from Archaea.