Question

2. Answer ALL parts a) f a) If the Prebiotic Earth had an oxygen-rich atmosphere, would this have interfered with the origin of life? Briefly explain your answer. b) Generation of biopolymers (e.g. nucleic acids and proteins) from the corresponding monomers often requires loss of a water molecule for each polymeric linkage that is made. What significance could be attached to this observation as it concerns the origin of life? c) Why is it widely believed that nucleic acids came before proteins in the chronology of the origin of life on Earth? d) Comment on the stability of mRNA, rRNA and tRNA in cells and how this affects protein synthesis. e) It is commonly believed that RNA preceded DNA in evolution. For what reason(s) was there an evolutionary advantage for DNA? f) What property of the first ribozyme discovered by Tom Cech prevents us from regarding it as a true enzyme?

Answer 1

A) Yes, oxygen is most important need for live to happen. Earlier, cyanobacteria was found to have photosynthetic activity which helped in maintaining the oxygen levels. Many together make up a cell or an organism.

B) Origin of life happend after a series of chemical reactions. Monomeric nucleotide join together to form polynucleotide which make up the DNA and RNA. These nucleci acid are most important as it is required for transfer to information from cell to cell. Also it is which is responsible for the recombination that happens in the chromosome which leads to evolution.

C) nucleic acid guide the protien synthesis and assembly of the amino acids. Many varitiy of proteins are formed from DNA.

D) RNA stability is nothing but the extant to which it can maintain its structural integrity. Ribosomal RNA is most stable and mRNA is the least stable. Halflives of these RNA definitely have an impact on translation. These are all involved in the protein synthesis and resisting degradation by the RNAse determines where a particular protein is produced or not .