* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download DNA Review
Holliday junction wikipedia , lookup
DNA barcoding wikipedia , lookup
DNA sequencing wikipedia , lookup
Comparative genomic hybridization wikipedia , lookup
Agarose gel electrophoresis wikipedia , lookup
Molecular evolution wikipedia , lookup
Community fingerprinting wikipedia , lookup
DNA vaccination wikipedia , lookup
Bisulfite sequencing wikipedia , lookup
Vectors in gene therapy wikipedia , lookup
Maurice Wilkins wikipedia , lookup
Gel electrophoresis of nucleic acids wikipedia , lookup
Non-coding DNA wikipedia , lookup
Molecular cloning wikipedia , lookup
Transformation (genetics) wikipedia , lookup
Cre-Lox recombination wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
CHAPTER 12 DNA: STRUCTURE AND FUNCTIONS I. The Genetic Material A. Early researchers knew that the genetic material must be: 1. able to store information used to control both the development and the metabolic activities of cells; 2. stable so it can be replicated accurately during cell division B. Transformation of Bacteria Bacteriologist Frederick Griffith (1931) experimented with Streptococcus pneumoniae (a pneumococcus that causes pneumonia in mammals). C. DNA: The Transforming Substance Oswald Avery et al. (1944) reported that purified DNA is capable of bringing about the transformation. D. Reproduction of Viruses Alfred Hershey and Martha Chase (1952) studied bacteriophage T2. II. The Structure of DNA A. Nucleotide Data Erwin Chargaff (1940s) analyzed the base content of DNA. B. Diffraction Data Rosalind Franklin produced X-ray diffraction photographs. C. The Watson and Crick Model 1. DNA as a double helix with sugar-phosphate groups on the outside, and paired bases on the inside. 2. Their model was consistent with both Chargaff’s rules and Franklin’s X-ray diffraction studies. 3. Complementary base pairing is the paired relationship between purines and pyrimidines in DNA: A is hydrogen-bonded to T and G is hydrogen-bonded to C. III. Replication of DNA: A. Replication is Semiconservative Matthew Meselson and Franklin Stahl (1958) confirmed B. In test tube, DNA replication requires the following. 1. DNA template; 2. Primer 3. dNTPs (dATP, dCTP, dGTP, dTTP) 4. DNA polymerase C. Heat resistant DNApolymerase, such as Taq DNA polymerase is used in Polymerase Chain Reaction (PCR) that is the base of forensic DNA analysis D. In vivo DNA synthesis: 1. Replication in eukaryotes starts at many points of origin and spreads with many replication bubbles—places where the DNA strands are separating. 2. It needs many more factors, unlike the replication in vitro. 3. Eukaryotes replicate their DNA at a slower rate – 500 to 5,000 base pairs per minute so that they take hours to complete DNA replication. 4. DNA polymerase is a Holo-enzyme, a complex of proteins, that has proof-reading functions. Review Qs: 1. If a DNA sample contains 13% adenine, what percentage of the sample contains cytosine? 2. Chargaff's rules states that __________________________________. 3. The DNA structure can be described as ___________________________________. The building blocks (monomers) are _____________________. On the outside of the helix are ____________________. On the inside of the helix are ________________________. Its 5’ end has _______________ and its 3’ end has _____________________. 4. If a DNA sequence 5’-ATTCCGATTCT-3’ is replicated, what is the sequence of the product? 5. In test tube, what is required for DNA synthesis? 6. Inside the cell, what are required for DNA synthesis in addition to what needed in test tube? 7. The fashion of DNA replication is _____________________. 8. What are required for DNA replication in vitro? 9. What are required for DNA replication in vivo? 10. What is the error rate in DNA replication?