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How does DNA work?

How does DNA work?

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How does DNA work?

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  1. How does DNA work?

  2. The “Central Dogma”

  3. The “Central Dogma”

  4. The “Central Dogma”

  5. The “Central Dogma”

  6. RNA Five differences between RNA and DNA • Sugar in RNA is ribose instead of deoxyribose • RNA is single stranded • RNA contains Uracil instead of Thymine • RNA is disposable • RNA can be outside the nucleus, DNA can’t If you are going from DNA to RNA – what nitrogenous base would pair with Adenine? DNA: C A G T T A RNA: _ _ _ _ _ _

  7. ANSWER: DNA: C A G T T A RNA: G U C A A U

  8. Types of RNA • Key players in Protein Synthesis - • Messenger RNA (mRNA): carry instruction copies • Ribosomal RNA (rRNA): makes up ribosome along with proteins • Transfer RNA (tRNA): brings amino acids to the ribosome

  9. Big picture of protein synthesis

  10. Transcription

  11. Translation

  12. Just Like Construction… • DNA is the master plan • mRNA is the everyday blueprint • rRNA is the builder • tRNA is the gopher • Amino Acids are the wood • Proteins are the building

  13. Translation of the Genetic Code - Protein Synthesis

  14. A U G G G C U U A A A G C A G U G C A C G U U • This is a molecule of messenger RNA. • mRNA is transcribed in the nucleus. codon mRNA molecule

  15. ribosome A U G G G C U U A A A G C A G U G C A C G U U A ribosome attaches to the mRNA molecule.

  16. Amino acid tRNA molecule anticodon U A C A U G G G C U U A A A G C A G U G C A C G U U A transfer RNA molecule arrives. It brings a specific amino acid to the first three bases (codon) on the mRNA. The three unpaired bases (anticodon) on the tRNA link up with the codon.

  17. U A C C C G A U G G G C U U A A A G C A G U G C A C G U U Another tRNA molecule comes into place, bringing a second amino acid. Its anticodon links up with the second codon on the mRNA.

  18. Peptide bond C C G U A C A U G G G C U U A A A G C A G U G C A C G U U A peptide bond forms between the two amino acids.

  19. C C G U A C A U G G G C U U A A A G C A G U G C A C G U U The first tRNA molecule releases its amino acid and moves off into the cytoplasm.

  20. C C G A U G G G C U U A A A G C A G U G C A C G U U The ribosome moves along the mRNA to the next codon.

  21. C C G A A U A U G G G C U U A A A G C A G U G C A C G U U Another tRNA molecule brings the next amino acid into place.

  22. C C G C C G A U G G G C U U A A A G C A G U G C A C G U U A peptide bond joins the second and third amino acids to form a polypeptide chain.

  23. G U C A C G A U G G G C U U A A A G C A G U G C A C G U U The process continues. The polypeptide chain gets longer. This continues until a termination (stop) codon is reached. The polypeptide is then complete.

  24. CODON TABLE

  25. 1. What amino acids would be coded by the following DNA sequence? CGGACCGCTATC 2. What would be the DNA sequence for a polypeptide chain (protein) that had the following amino acids? Lysine-Cysteine-Proline