1 / 15

Bell ringer: Briefly describe DNA transcription and translation.

Bell ringer: Briefly describe DNA transcription and translation. Comparing DNA and RNA. Transcription + Translation = Protein Synthesis. Transcription. Takes place in the nucleus RNA polymerase unwinds helix One strand of DNA acts as a template for mRNA (messenger RNA)

neveah
Download Presentation

Bell ringer: Briefly describe DNA transcription and translation.

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. Bell ringer:Briefly describe DNA transcription and translation.

  2. Comparing DNA and RNA

  3. Transcription + Translation =Protein Synthesis

  4. Transcription • Takes place in the nucleus • RNA polymerase unwinds helix • One strand of DNA acts as a template for mRNA (messenger RNA) • Promoter: marks where transcription starts • Intron: non-coding region, becomes pre-mRNA • Exon: coding region, becomes mature mRNA • Terminator: marks where transcription ends • After transcription is complete, the mRNA molecule detaches from the DNA and leaves the nucleus through pores • DNA helix reforms

  5. Transcription

  6. Translation • Takes place at the ribosome (made of rRNA) in the cytoplasm • tRNA (transfer RNA) carries anti-codons to ribosome where it is matched with a codon • Activation – start codon AUG • Codon-anticodon binding leads to polypeptide formation

  7. Triplets, codons and anti-codons,OH MY! • Triplet = group of three DNA nucleotides • Codon = group of three mRNA nucleotides • Anti-codon = group of three tRNA nucleotides • There are 64 anti-codons • There are 20 amino acids

  8. One Gene = One PolypeptideHypothesis • Theory: one gene is transcribed and translated to produce one polypeptide • Some proteins are composed of more than one polypeptide; this theory says that each polypeptide has its own gene • Example: hemoglobin – composed of four polypeptides (two copies of two types), each polypeptide has its own gene.

  9. Exceptions to the theory- • Some genes code for types of RNA that do not produce polypeptides • Some genes control the expression of other genes

More Related