our guiding question n.
Skip this Video
Loading SlideShow in 5 Seconds..
Our Guiding Question PowerPoint Presentation
Download Presentation
Our Guiding Question

Loading in 2 Seconds...

play fullscreen
1 / 11

Our Guiding Question - PowerPoint PPT Presentation

Download Presentation
Our Guiding Question
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


  2. Warm-up • Which parts of the nucleotides are connected to make one strand (half) of DNA? • Which parts of the nucleotides connect the two strands (halves) of DNA? • What type of bond connects the two strands together? • If a DNA molecule is 30%Adenine how much Cytosine is there?

  3. What does DNA look like? • We can describe its molecular structure • We can say what DNA looks like after isolation.

  4. DNA replication How is DNA made?

  5. DNA Replication Whenever a cell divides into two new cells, it needs to make an exact copy of the DNA. What would happen if a cell divided without DNA making a copy of itself? The process of copying DNA is calledDNA replication.

  6. Enzymes in DNA replication • Enzymes are proteins that act as machines in the cell to do work. • 2 enzymes do the work of DNA replication: • Helicase is responsible for separating the 2 strands of DNA • DNA Polymerase is responsible for adding on new Nucleotides. We will replicate (copy) our DNA molecule in class to produce 2 new identical DNA molecules

  7. Helicase • Helicase unwinds and separates the 2 strands of DNA so that each strand may be copied. • Helicase breaks the hydrogen bonds between the bases of each strand. Hydrogen Bonds

  8. DNA Polymerase • DNA Polymerase adds on the complimentary bases to the new strands of DNA • DNA Polymerase makes bonds between the phosphate and the deoxyribose sugar of the nucleotides. DNA Polymerase

  9. Complementary base pairing • If one strand of DNA has the following sequence, CTAATGT GATTACA What is the base sequence (order of nucleotides) for the complimentary strand?

  10. Complicated picture of replication…

  11. Replication in Action • Replication occurs simultaneously at multiple places along a DNA strand. • 1 chromosome is about 80 million base pairs long. • Replication is as fast as 50 base pairs a second! Flash Animation: http://www.mcb.harvard.edu/Losick/images/TromboneFINALd.swf