1 / 9

Chapter 10

Chapter 10. Do Now: Read 182-183. 1 ) Define bacteriophages 2) Why are viruses on the fence between life and nonlife ? 3) What are we going to explore in this chapter ? . 10.1 Experiments that showed that DNA is the genetic material. 1928: Griffith

kedma
Download Presentation

Chapter 10

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 10

  2. Do Now: Read 182-183 • 1) Define bacteriophages • 2) Why are viruses on the fence between life and nonlife? • 3) What are we going to explore in this chapter?

  3. 10.1 Experiments that showed that DNA is the genetic material • 1928: Griffith • Two strains of a bacteria (one strain caused pneumonia and the other strain was harmless) • Exp: heat killed harmful bacteria mixed with living harmless bacteria • Result: living harmful bacteria • What can we conclude from this experiment?

  4. 1940: Scientists knew that eukaryotic chromosomes were made of protein and DNA • Why did most scientists think that protein was the genetic material? • Proteins • are made up of 20 different amino acids • Can have complex structure and functions • DNA is simple • Four nucleotides

  5. 1952: Alfred Hershey& Chase pg 185 • T2 virus is made of DNA and protein • Batch 1) Grew virus in radioactive* sulfur (proteins contain sulfur and DNA does not) • Batch 2) Grew virus in radioactive* phosphorus (phosphate w/oxygen) • Steps: • 1) Allowed batches to attack bacteria • 2) Shook off any outside viral parts • 3) Spun with centrifuge, cells to the bottom • 4) Measured radioactivity in liquid vs. pellet • Result: Batch 1: protein* on the outside Batch 2: DNA* in cell • Conclusion:

  6. 10.2: DNA and RNA Description • What is DNA? A biological code to make proteins that can be passed from one generation to the next • Deoxyribonucleic Acid • DNA is made up of nucleotides (sugar (deoxyribose, phosphate and a nitrogenous base) • Polynucleotide is many nucleotides join to form a long chain of DNA • RNA uses ribose as sugar, uracil in place of thymine, and is single stranded

  7. 10.3 DNA 3D model discovered by Watson/ Crick and Rosalind Franklin What does DNA look like? A double helix- similar to a twisted ladder • The sides are made up of the sugar and phosphates (backbone) • The rungs of the ladder are made up of the nitrogenous bases held together by hydrogen bonds • The four bases are Adenine (A), Guanine (G), Thymine(T) and Cytosine (C) • Complementary base pairing Pyrimidine- purine • Adenine bonds to thymine (T-A) • Guanine bonds to Cytosine (G-C) • DNA is wrapped around proteins called histones to create the condensed form called chromatin • DNA is able to mutate slightly overtime to allow for variation and evolution

  8. 10.2 A-B Draw the following structures on page 186 and 187 • Polynucleotide • Sugar phosphate backbone • DNA nucleotide • Pyrimidines • Purines • HW: Exercise 1 in packet

More Related