Bioguider

  translation refers to the process by which a cell synthesizes proteins based on the genetic instructions encoded in messenger RNA (mRNA). This is one of the key steps in gene expression and involves converting the nucleotide sequence of mRNA into the amino acid sequence of a protein. The main steps in molecular biology translation are: Initiation : The ribosome (the cell's protein synthesis machinery) assembles around the start codon of the mRNA, which is usually AUG. This codon signals the beginning of protein synthesis and recruits the first transfer RNA (tRNA) carrying the amino acid methionine. Elongation : The ribosome reads the mRNA sequence codon by codon (three nucleotide bases at a time), and corresponding tRNAs bring the correct amino acids. Each codon on the mRNA corresponds to a specific amino acid, and the tRNA molecules, which carry these amino acids, have anticodons that match the codons on the mRNA. Peptide Bond Formation : As the ribosome moves along the mRNA, t...

 Transcription is a fundamental biological process in which the genetic information in a DNA sequence is copied into a complementary RNA sequence. This is the first step in gene expression, leading to the production of proteins. Steps of Transcription Initiation Transcription begins when RNA polymerase, an enzyme, binds to a specific DNA region called the promoter . The promoter is located upstream of the gene that is to be transcribed. The binding of RNA polymerase to the promoter causes the DNA to unwind, forming a small open complex known as the transcription bubble . Elongation : RNA polymerase moves along the DNA template strand in the 3’ to 5’ direction, synthesizing a single-stranded RNA molecule in the 5’ to 3’ direction. As it moves, RNA polymerase adds RNA nucleotides (adenine, uracil, cytosine, and guanine) complementary to the DNA template strand. For example, if the DNA has a cytosine (C), the RNA will have a guanine (G). Termination : Transcription continues u...