DNA, mRNA, Codons

To manufacture protein molecules, a cell must first transfer information from DNA to mRNA through the process of transcription. Then, a process called translation uses this mRNA as a template for protein assembly. In fact, this flow of information from DNA to RNA and finally to protein is considered the central dogma of genetics, and it is the starting point for understanding the function of the genetic information in DNA. But just how does translation work? In other words, how does the cell read and interpret the information that is stored in DNA and carried in mRNA? The answer to this question lies in a series of complex mechanisms, most of which are associated with the cellular structure known as the ribosome. In order to understand these mechanisms, however, it’s first necessary to take a closer look at the concept known as the genetic code. Redundancy in the genetic code means that most amino acids are specified by more than one mRNA codon. For example, the amino acid phenylalanine (Phe) is specified by the codons UUU and UUC, and the amino acid leucine (Leu) is specified by the codons CUU, CUC, CUA, and CUG. Methionine is specified by the codon AUG, which is also known as the start codon. Consequently, methionine is the first amino acid to dock in the ribosome during the synthesis of proteins. Tryptophan is unique because it is the only amino acid specified by a single codon. The remaining 19 amino acids are specified by between two and six codons each. The codons UAA, UAG, and UGA are the stop codons that signal the termination of translation. Problems: Which of the following molecular structures contain codons? A) a protein B) tRNA C) rRNA D) mRNA According to the central dogma, what is the intermediate molecule involved in the flow of information in a cell that should go in the blank? DNA → ________ → Proteins A)tRNA B) mRNA C) rRNA D) mtDNA #mRNA #DNA #codons #Genetics #proteins #aminoAcids #nucleicAcids #RNA #biology #transcription #translation #polypeptide #enzyme #codon #nucleotide #codonTable #aminoAcid #rybosome #tRNA #anticodon #rRNA #TransferRNA #GeneticsFieldOfStudy #antiCodon #stopCodon #startCodon #AnticodonAndCodon #anticodonLoop #anticodonWooble #anticodonSequence #basePairs #protein #typesOfRNA #codonChart #RNAPolymerase #transcriptionVsTranslation
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