1 / 26

Chapter 7, Part 1: The Blueprint of Life, from DNA to Protein

Chapter 7, Part 1: The Blueprint of Life, from DNA to Protein. 2 Minute Brainstorm. Put these terms in order as they occur: RNA Transcription DNA Protein Translation. Transcription. DNA. Translation. Protein. RNA. Question 1: What is DNA Made Up Of (Subunits)?. 2. What are the bases?.

tahlia
Download Presentation

Chapter 7, Part 1: The Blueprint of Life, from DNA to Protein

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. Chapter 7, Part 1:The Blueprint of Life, from DNA to Protein

  2. 2 Minute Brainstorm • Put these terms in order as they occur: • RNA • Transcription • DNA • Protein • Translation Transcription DNA Translation Protein RNA

  3. Question 1: What is DNA Made Up Of (Subunits)? 2. What are the bases? Sugar ≠ Supercoil (Fix this by eliminating O!) Why deoxy? Hydroxyl groups have what charge? Phosphate have what charge? Negative REPEL!

  4. Question 2: How do the subunits link together? Only 1 gets incorporated and the release of energy by breaking the bonds helps give “fuel” to form the phosphodiester backbone 2. What happens to the phosphates and why? Sugar 1. How are the subunits linked together? 5’ PO4 to 3’ OH LABEL THE CARBONS!

  5. Question 3: How do the strands link together? 1. How are the bases paired together? H? LABEL THE CARBONS! Sugar 2. What are the orientation of the strands? Antiparallel!

  6. Question Given the amount of Adenine in a DNA sample is 37%, what is the amount of cytosine? A. 37% B. 13% C. 74% D. 50%

  7. Individual and Group Work (5 mins) • Work by yourself for 2 minutes and fill out the work sheet • Then compare your answers with your partner

  8. 3’ 5’ 2 T 5 1 4 2 2 3 Phosphate A Sugar 3 C 3 G 5’ 3’

  9. Why do prokaryotes replicate DNA?

  10. Bacteria Have Circular DNA! Do Eukaryotes? NO! “Bidirectional” Why? TIME IS PRECIOUS!

  11. How Is Replication Initiated? • Must have Origin of Replication (ori) • Region of specific base pairs “code” • No ori=no replication! • ~20 initiator proteins bind to ori-facilitate melting A-T Rich! WHY? Takes less energy to separate 2 H bonds than 3!

  12. DNA Is Open at the Ori…Now What? 2. 3. Why doesn’t DNA Polymerase just start synthesizing? NEEDS A PRIMER!!! RNA Primase has to do its job 1st

  13. Synthesis Occurs In Leading and Lagging Strands Has primer, replication and unwinding is going in the correct direction for continuous synthesis: opening up so can lay down more 3’ WHY? 4. WHY? 5. Can only lay down short tracks…opening in the 5’ direction

  14. Filling In the Gaps 6. 5.

  15. Question • Identify the leading and lagging strand

  16. Supercoiling Can Be A Problem…DNA Gyrase to the Rescue! How do we solve the problem? DNA Gyrase http://www.youtube.com/watch?v=3QWA-tFdGN8 (1:21)

  17. How Do We End DNA Replication? • Just like initiation of replication, termination is governed by a termination site • In this site, a protein binds and prevents helicase activity

  18. Just Like Eukaryotes, Bacteria DNA Replication is Semiconservative

  19. How are genes encoded in DNA actually expressed? • 2 steps: • Transcription (DNARNA) • Is the language mostly the same? Yes • Think transcribe: “re-write” • Translation (RNAprotein) • Is the language mostly the same? No • Think translate/decipher: to express in another language

  20. Question 1: What Is RNA Made Up Of (Subunits)? 2. What are the bases? ≠ Supercoil (why it is single stranded!) Why the hydroxyl group? Hydroxyl groups have what charge? Phosphate have what charge? Negative REPEL!

  21. Question 2: What Are The Types of RNA and Their Purpose? *Important in translation rRNA mRNA *Holds encrypted information tRNA *Important in translation

  22. How Is Transcription Initiated? • RNA Polymerase recognizes a specific sequence in the DNA (promoter) • Sigma factor is the portion of the polymerase that recognizes the promoter • Promoters are upstream of the genes they control • Binding causes DNA to melt

  23. Promoters Can Be In Both Directions! • The direction of the promoter dictates the template strand • How can you figure out the template strand? • First, what direction does the RNA Polymerase go? 5’ to 3’ • Then, the template (-) strand will be the opposite!

  24. Elongation of the Transcript • RNA Polymerase moves along the DNA, melting it, and adding nucleotides at the 3’ end • Base pairing: A=U, G=C • Once RNA Polymerase has cleared the promoter, another molecule of the enzyme can bind and start again!

  25. How Do We End Transcription? • Just like initiation of transcription, termination is governed by a termination site • In this site, the RNA polymerase stalls and releases

  26. Homework & Muddiest Point Homework Due At the Start of Class (Friday!) No late, no make-ups! Hand-In Questions!

More Related