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How does the process of RNA transcription and translation contribute to the synthesis of proteins in living organisms, and what are the specific chemical reactions involved in this process?

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RNA transcription and translation are essential processes in living organisms that contribute to the synthesis of proteins. These processes involve the conversion of genetic information stored in DNA into functional proteins, which are the workhorses of the cell, carrying out various structural, enzymatic, and regulatory functions.1. RNA Transcription:Transcription is the process by which the genetic information in DNA is copied into a complementary RNA molecule. This process is catalyzed by the enzyme RNA polymerase, which synthesizes the RNA molecule in a 5' to 3' direction. The specific chemical reactions involved in transcription are as follows:a. Initiation: RNA polymerase binds to a specific DNA sequence called the promoter, which is located upstream of the gene to be transcribed. This binding causes the DNA double helix to unwind, creating a transcription bubble.b. Elongation: RNA polymerase adds ribonucleotide triphosphates  rNTPs  to the growing RNA chain, complementary to the DNA template strand. The enzyme catalyzes the formation of phosphodiester bonds between the ribonucleotides, releasing pyrophosphate  PPi  in the process. This reaction can be represented as: NMP n + rNTP   NMP n+1 + PPiwhere NMP represents the ribonucleotide monophosphate and n is the number of nucleotides in the RNA chain.c. Termination: Transcription continues until RNA polymerase reaches a specific DNA sequence called the terminator. At this point, the RNA molecule is released, and the DNA double helix re-forms.2. RNA Translation:Translation is the process by which the information in the RNA molecule, specifically messenger RNA  mRNA , is used to synthesize proteins. This process occurs in the ribosome and involves transfer RNA  tRNA  molecules and various translation factors. The chemical reactions involved in translation can be divided into three main steps:a. Initiation: The ribosome assembles around the mRNA molecule, with the small ribosomal subunit binding to the mRNA's 5' end. The initiator tRNA, carrying the amino acid methionine, binds to the start codon  AUG  on the mRNA. The large ribosomal subunit then associates with the small subunit, forming the complete ribosome.b. Elongation: The ribosome moves along the mRNA, reading the codons  three-nucleotide sequences  and recruiting the appropriate tRNA molecules carrying their respective amino acids. The amino acids are joined together by peptide bonds, which are formed through a dehydration reaction:Amino acid 1 + Amino acid 2  Dipeptide + H2OThis reaction is catalyzed by the ribosome, and the growing polypeptide chain is transferred from the tRNA in the ribosome's P site to the incoming tRNA in the A site.c. Termination: Translation continues until the ribosome encounters a stop codon  UAA, UAG, or UGA  on the mRNA. At this point, a release factor protein binds to the stop codon, causing the ribosome to release the completed polypeptide chain. The ribosome then dissociates into its subunits, and the mRNA is released.In summary, RNA transcription and translation are crucial processes in living organisms that enable the synthesis of proteins from the genetic information stored in DNA. These processes involve a series of specific chemical reactions, including the formation of phosphodiester bonds during transcription and peptide bonds during translation.
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