1 / 14

Ribosomes and Protein Synthesis

Ribosomes and Protein Synthesis. Learning Objectives. Identify the genetic code and explain how it is read. Summarize the process of translation. Describe the central dogma of molecular biology. The Genetic Code.

loehr
Download Presentation

Ribosomes and Protein Synthesis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ribosomes and Protein Synthesis

  2. Learning Objectives • Identifythe genetic code and explain how it is read. • Summarizethe process of translation. • Describethe central dogma of molecular biology.

  3. The Genetic Code RNA has four bases: adenine, cytosine, guanine, and uracil. These bases form a “language”: A, C, G, and U.

  4. The Genetic Code: Codons The genetic code is read in three-letter groupings called codons. A codon is a group of three nucleotide bases in messenger RNA that specifies a particular amino acid. AAC UCU AUG

  5. Genetic Code Table There are 64 possible three-base codons in the genetic code.

  6. Reading Codons Start at the middle of the circle with the first letter of the codon and move outward. CAC = Histidine

  7. Start and Stop Codons The methionine codon AUG serves as the “start” codon for protein synthesis. There are three “stop” codons. UAA, UAG, and UGAare “stop” codons AUG = methionine = “start” codon

  8. Translation Transcribed mRNA directs the translation process. Translation is the process that produces proteins by decoding the sequence of mRNA codons.

  9. Translation: Transfer RNA Translation starts when a ribosome attaches to an mRNA molecule. Then, tRNA molecules, carrying amino acids with them, bind to mRNA codons. anticodon

  10. Translation: The Polypeptide Assembly The ribosome helps form a peptide bond. It breaks the bond holding the first tRNA molecule to its amino acid.

  11. Translation: Completing the Polypeptide The ribosome reaches a stop codon, releasing the newly synthesized polypeptide and the mRNA molecule, completing the process of translation.

  12. Roles of RNA in Translation All three major forms of RNA—mRNA, tRNA, and rRNA—are involved in the process of translation.

  13. The Molecular Basis of Heredity The central dogma of molecular biology is that information is transferred from DNA to RNA to protein.

  14. Gene Expression When a gene (segment) of DNA code is used to build a protein, scientists say that gene has been expressed.

More Related