Rna transcription and the genetic code
Download
1 / 13

RNA, Transcription, and the Genetic Code - PowerPoint PPT Presentation


  • 103 Views
  • Uploaded on

RNA, Transcription, and the Genetic Code. RNA. RNA = ribonucleic acid Nucleic acid similar to DNA but with several differences. *Uracil replaces Thymine in RNA and base pairs with Adenine!. RNA. Types of RNA: Messenger RNA (mRNA) - carries DNA message out of nucleus to ribosomes

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' RNA, Transcription, and the Genetic Code' - yamka


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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

RNA

  • RNA = ribonucleic acid

  • Nucleic acid similar to DNA but with several differences

*Uracil replaces Thymine in RNA and base pairs with Adenine!


RNA

  • Types of RNA:

  • Messenger RNA (mRNA)

  • - carries DNA message out of nucleus to ribosomes

  • 2. Ribosomal RNA (rRNA)

  • - found in ribosomes

  • 3. Transfer RNA (tRNA)

  • - contain anti-codons used in translation, brings amino acid to ribosome


Transcription

  • Transcription = process of making an mRNA strand from DNA

  • Similar to replication but remember, RNA is single stranded not double stranded.

  • Enzyme involved is called RNA polymerase.


Transcription

  • Steps:

  • Initiation

    • RNA polymerase binds to promoter region of DNA strand.

    • Promoter = region of DNA that signals the start of a gene

  • 2. Elongation

    • RNA polymerase creates a 5’ to 3’ mRNA strand using DNA as a template.


Transcription

  • Steps:

  • 3. Termination

  • RNA polymerase reaches end of DNA sequence that codes for gene (Termination sequence) and releases mRNA into nucleus.

  • Transcription Animation



RNA Splicing

Before mRNA strand is sent out of the nucleus. Non-coding parts need to be taken out through RNA splicing.

Introns= Non-coding segments, taken out

Exons= Coding segments, spliced together

mRNA Splicing Video



The Genetic Code

  • * Proteins are made when mRNA molecule travels out of nucleus to cytoplasm to ribosomes.

  • Proteins are mode by joining amino acids together into long chains called polypeptides.

  • Order of amino acids determines the properties of the protein.


The Genetic Code

  • A, G, C, and U bases of RNA form a “language” called the Genetic Code.

    • It is universal

Codon = every three letters on an mRNA strand.


The Genetic Code

* Genetic code is degenerate since 64 different combinations of letter code for only 20 different amino acids. That means that most amino acids can be specified by more than one codon.

Important codons are start and stop:

Start = AUG

Stop = UAA, UGA, UAG



ad