1 / 12

Where is DNA found within the cell?

Where is DNA found within the cell? . Quick Question #1. Lets refresh our knowledge of DNA structure http://www.youtube.com/watch?v=ZGHkHMoyC5I. What occurs during the cell cycle? . Quick Question #2. DNA REPLICATION. Copying of DNA An extremely precise process

gerik
Download Presentation

Where is DNA found within the cell?

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. Where is DNA found within the cell? Quick Question #1 Lets refresh our knowledge of DNA structure http://www.youtube.com/watch?v=ZGHkHMoyC5I

  2. What occurs during the cell cycle? Quick Question #2

  3. DNA REPLICATION • Copying of DNA • An extremely precise process • Copies in sections, not from one end to the other • Basis of biological inheritance

  4. Replication Process • Three step process • Each step controlled by one of three enzymes (enzymes always end in –aseso look out for them in these notes) • Directional: always starts at a 5’ end of DNA strands and builds onto the 3’ end: • Copies both strands simultaneously starting at the replication fork.

  5. What do you think needs to happen in order for replication to start Quick Question #3

  6. Replication: Step One Facilitated by: Helicase • Helicase enzyme unwinds and unzips DNA strands • breaks hydrogen bonds QQ#4 What do you think will needs to happen for the DNA to “unzip”?

  7. A G G C T C C G DNAPolymerase Replication: Step Two Facilitated by: DNA Polymerase • DNA Polymerase enzyme: • reads a base on one side • Then adds complementary (matching) base to the other • e.g.

  8. Step 2 Continued • Both sides replicated to create two new strands of DNA each with: • -One original and One new strand

  9. Step 2 Continued • Strands are replicated from 5’ to 3’ and go in opposite directions • One side is replicated in a continuous piece: • -Leading Strand • Other side is replicated in short pieces: • -Lagging Strand • Okazaki Fragments

  10. Replication: Step Three Facilitated by: Ligase • Ligase enzyme • Glues (ties) DNA all together • Very important for Okazaki Fragments-closes any gaps between them

  11. Draw a visual that helps YOU remember the 3 steps of replication Quick Question #5

  12. Overall Process of Replication http://www.youtube.com/watch?v=teV62zrm2P0

More Related