Medical Physiology - The Transcription Process in the Cell Cytoplasm

Medical Physiology - The Transcription Process in the Cell Cytoplasm
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In the cell nucleus, DNA code is converted to RNA.Since the cytoplasm is where many of the cell's tasks are performed and DNA is found in the nucleus, there must be a mechanism by which the genes in the nucleus regulate the cytoplasm's chemical reactions. This is accomplished by RNA, whose synthesis is regulated by DNA. In this procedure, known as transceiption I, the DNA information is converted to RNA. The transcription of Introduction to Physiology: The Cell and General Physiology. The RNA regulates protein production in the cytoplasm after diffusing from the nucleus to the nuclear pores. The nucleus uses a DNA template to synthesize RNA. The DNA molecule's two strands split apart during the production of RNA, and one of the two strands is utilized as a template. The complementary code triplets (known as codons) that are formed in the RNA as a result of the code triplets in the DNA regulate the amino acid sequence of proteins that are subsequently made in the cytoplasm.
The coding for up to 2000–4000 genes is carried by each DNA strand in each chromosome. With the exception of the substitution of the sugar ribose for the sugar deoxyribose and the substitution of pyrimidine uracil for thymine, the fundamental building components of RNA and DNA are nearly identical.
As with the creation of DNA, the fundamental building components of RNA unite to generate four nucleotides. The bases adenine, guanine, cytosine, and uracil are present in these nucleotides. Activation of the nucleotides is the subsequent stage in the creation of RNA. Tri-phosphates are created when two phosphate radicals are added to each nucleotide. High-energy phosphate bonds, which are produced from the cell's adenosine triphosphate (ATP), join these final two phosphates to the nucleotide. Large amounts of energy are made available by this activation step, and they are utilized to support the chemical reactions that add each new RNA nucleotide to the end of the RNA chain.

The RNA molecule is assembled from activated nucleotides using the DNA strand as a template. Under the influence of the RNA polymerase enzyme, the RNA molecule is assembled as follows: 1. A series of nucleotides known as the promoter is located on the DNA strand just in front of the gene that needs to be transcribed. This promoter is recognized by an RNA polymerase, which binds to it. 2. The polymerase causes the DNA helix's two turns to unwind, separating the unwound sections. 3. By attaching complementary RNA nucleotides to the DNA strand, the polymerase travels down the DNA strand and starts creating the RNA molecules. 4. An RNA strand is created when the subsequent RNA nucleotides attach to one another. 5. The RNA polymerase breaks away from the DNA strand when it comes across the chain-terminating sequence, a collection of DNA molecules, near the end of the DNA gene. After then, the RNA strand is discharged into the nucleoplasm. The RNA molecule receives the complementary form of the code found in the DNA strand in the manner described below:
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The four main forms of RNA each have distinct functions in the synthesis of proteins: Activated amino acids are transported to the ribosomes by transfer RNA (tRNA) to be used in the assembly of the proteins; messenger RNA (mRNA) carries the genetic code to the cytoplasm to control the formation of proteins; ribosomal RNA and proteins form the ribosomes, the structures in which protein molecules are assembled; and microRNA (miRNA), which are single-stranded RNA molecules of 21–23 nucleotides that can regulate gene transcription and translation.

Each of the 20 different forms of tRNA binds to one of the 20 amino acids in a particular way before transporting the amino acid to the ribosomes, where it is integrated into the protein molecule. The triplet of nucleotide bases known as an anticodon is the code in the tRNA that enables it to identify a particular codon. By forming hydrogen bonds with the mRNA's codon bases, the three anticodon bases loosely assemble to form the protein molecule. This creates the correct amino acid sequence in the protein molecule by aligning the different amino acids along the mRNA chain.