copyright cmassengale

Slides:



Advertisements
Similar presentations
DNA and Replication.
Advertisements

1 DNA and Replication. 2 History of DNA Early scientists thought protein was the hereditary material –Protein is more complex than DNA –Proteins are composed.
1 DNA Replication copyright cmassengale. 2 Replication Facts DNA has to be copied before a cell dividesDNA has to be copied before a cell divides DNA.
1 DNA and Replication copyright cmassengale. 2 History of DNA copyright cmassengale.
1 DNA and Replication copyright cmassengale. 2 Antiparallel Strands One strand of DNA goes from 5’ to 3’ (sugars) The other strand is opposite in direction.
copyright cmassengale
1 Aim #16: How does a DNA molecule replicate itself?
1 History of DNA. 2 DNA Structure Rosalind Franklin took diffraction x-ray photographs of DNA crystals In the 1950’s, Watson & Crick built the first model.
History Of DNA and Replication
1 2 DNA DNA.DNA is often called the blueprint of life. In simple terms, DNA contains the instructions for making proteins within the cell.
1 DNA and Replication. 2 History of DNA 3 Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA Proteins.
1 DNA and Replication copyright cmassengale. 2 History of DNA copyright cmassengale.
1 DNA and Replication ubyIRiN84 DNA replication…3 min. WATCH, LISTEN AND COMPREHEND!!!!!!!
1 Structure and Replication Of DNA, DNA damage & repair Dr. Madhumita Bhattacharjee Assiatant Professor Botany deptt. P.G.G.C.G. -11,Chandigarh.
1 DNA Replication copyright cmassengale. 2 Replication Facts DNA has to be copied before a cell dividesDNA has to be copied before a cell divides DNA.
copyright cmassengale
1 DNA and Replication 2 History of DNA 3 Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA Proteins.
1 DNA and Replication. 2 DNA Structure 3 DNA Stands for Deoxyribonucleic acid nucleotidesMade up of subunits called nucleotides Nucleotide made of:Nucleotide.
1 DNA and Replication. 2 History of DNA 3 Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA Proteins.
1 DNA and Replication. SCI.9-12.B [Indicator] - Compare DNA and RNA in terms of structure, nucleotides, and base pairs. 2.
DNA and Replication 1. History of DNA 2  Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA 
1 DNA Structure and Replication. 2 DNA Two strands coiled called a double helix Sides made of a pentose sugar Deoxyribose bonded to phosphate (PO 4 )
copyright cmassengale
1 DNA and Replication. 2 Chargaff’s Rule Adenine ThymineAdenine must pair with Thymine Guanine CytosineGuanine must pair with Cytosine The bases form.
1 DNA and Replication copyright cmassengale. 2 History of DNA copyright cmassengale.
DNA. History of DNA Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA Proteins were composed of.
1 DNA and Replication copyright cmassengale. 2 History of DNA copyright cmassengale.
1 History of DNA copyright cmassengale. 2 History of DNA Early scientists thought protein was the cell’s hereditary material because it was more complex.
1 DNA Structure copyright cmassengale. 2 DNA Nucleotide O=P-O OPhosphate Group Group N Nitrogenous base (A, G, C, or T) (A, G, C, or T) CH2 O C1C1 C4C4.
History of DNA. Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA Proteins were composed of 20.
1 DNA and Replication copyright cmassengale. 2 History of DNA copyright cmassengale.
1 DNA and Replication copyright cmassengale. 2 History of DNA Early scientists thought protein was the cell’s hereditary material because it was more.
1 DNA and Replication. 2 History of DNA 3 Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA Proteins.
1 DNA and Replication. 2 History of DNA 3 Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA Proteins.
1 DNA and Replication. 2 History of DNA 3 Transformation Fred Griffith worked with virulent S and nonvirulent R strain Pneumoccocus bacteria He found.
DNA REPLICATION. Replication Facts DNA has to be copied before a cell divides DNA has to be copied before a cell divides DNA is copied during the S or.
1 DNA History Pt. 2 copyright cmassengale. 2 History of DNA Early scientists thought protein was the cell’s hereditary material because it was more complex.
1 DNA and Replication. 2 History of DNA 3 Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA Proteins.
1 DNA and Replication. 2 History of DNA 3 Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA Proteins.
1 DNA and Replication. 2 History of DNA 3 Early scientists thought protein was the cell’s hereditary material because it was more complex than DNA Proteins.
1 DNA and Replication copyright cmassengale. 2 History of DNA copyright cmassengale.
1 DNA and Replication copyright cmassengale. 2 History of DNA copyright cmassengale.
DNA Replication DNA → RNA → Protein replication
DNA and Replication.
DNA Replication.
copyright cmassengale
Adapted from cmassengale
DNA and Replication.
copyright cmassengale
DNA and Replication.
DNA and Replication.
copyright cmassengale
DNA Structure & Replication
DNA and Replication.
DNA Replication.
copyright cmassengale
copyright cmassengale
copyright cmassengale
12.1 DNA.
DNA and Replication.
DNA vs RNA DNA 1- Deoxyribose sugar
DNA Replication Essential Question: How do enzymes help ensure DNA is copied correctly?
DNA and Replication.
DNA Replication Unit 6 Topic 2
DNA and Replication.
DNA and Replication.
copyright cmassengale
DNA Replication Chapter 12 Section 2
Presentation transcript:

copyright cmassengale DNA and Replication copyright cmassengale

DNA Structure Continued copyright cmassengale

copyright cmassengale

copyright cmassengale Antiparallel Strands One strand of DNA goes from 5’ to 3’ The other strand is opposite in direction going 3’ to 5’ copyright cmassengale

copyright cmassengale DNA P P O 1 2 3 4 5 P O 1 2 3 4 5 G C T A copyright cmassengale

copyright cmassengale Question: If there is 30% Adenine, how much Cytosine is present? copyright cmassengale

copyright cmassengale Answer: There would be 20% Cytosine Adenine (30%) = Thymine (30%) Guanine (20%) = Cytosine (20%) Therefore, 60% A-T and 40% C-G copyright cmassengale

copyright cmassengale History of DNA copyright cmassengale

copyright cmassengale History of DNA Early scientists thought protein was the cell’s genetic material because it was more complex than DNA copyright cmassengale

copyright cmassengale Griffith Experiment copyright cmassengale

copyright cmassengale Transformation Fred Griffith worked with virulent S and nonvirulent R strain Pneumoccocus bacteria He found that R strain could become virulent when it took in DNA from heat-killed S strain Study suggested that DNA was probably the genetic material copyright cmassengale

copyright cmassengale DNA Structure Rosalind Franklin took diffraction x-ray photographs of DNA crystals In the 1950’s, Watson & Crick built the first model of DNA using Franklin’s x-rays copyright cmassengale

copyright cmassengale Rosalind Franklin copyright cmassengale

copyright cmassengale DNA Replication copyright cmassengale

copyright cmassengale DNA replication overview copyright cmassengale

copyright cmassengale Replication Facts DNA has to be copied before a cell divides DNA is copied during the S phase of interphase New cells will need identical DNA strands Mitosis G1 G2 S phase copyright cmassengale

copyright cmassengale DNA Replication Begins at Origins of Replication Two strands open forming Replication Forks (Y-shaped region) New strands grow at the forks Replication Fork Parental DNA Molecule 3’ 5’ copyright cmassengale

copyright cmassengale DNA Replication DNA replications is Semiconservative. Each new double-stranded DNA contains one old strand (template) and one newly-synthesized complementary strand copyright cmassengale

copyright cmassengale DNA Replication As the 2 DNA strands open at the origin, Replication Bubbles form Chromosomes have MANY bubbles Bubbles copyright cmassengale

DNA Replication Enzymes Helicase-unwinds and separates the 2 DNA strands by breaking the weak hydrogen bonds Single-Strand Binding Proteins- attach and keep the 2 DNA strands separated and untwisted copyright cmassengale

DNA Replication Enzymes Topoisomerase attaches to DNA ahead of the bubble to relieve stress on the DNA molecule as it separates. Video Enzyme DNA Enzyme copyright cmassengale

copyright cmassengale DNA Replication Before new DNA strands can form, there must be RNA primers present to start the addition of new nucleotides Primase is the enzyme that synthesizes the RNA Primer DNA polymerase III can then add the new nucleotides copyright cmassengale

Direction of Replication DNA Replication DNA polymerase can only add nucleotides to the 3’ end of the DNA This causes the NEW strand to be built in a 5’ to 3’ direction RNA Primer DNA Polymerase Nucleotide 5’ 3’ Direction of Replication copyright cmassengale

Synthesis of the New DNA Strands The Leading Strand is synthesized as a single strand from the point of origin toward the opening replication fork RNA Primer DNA Polymerase Nucleotides 3’ 5’ copyright cmassengale

Synthesis of the New DNA Strands The Lagging Strand is synthesized discontinuously against overall direction of replication This strand is made in MANY short segments It is replicated from the replication fork toward the origin RNA Primer Leading Strand DNA Polymerase 5’ 3’ Lagging Strand 5’ 3’ copyright cmassengale

Lagging Strand Segments Okazaki Fragments - series of short segments on the lagging strand Must be joined together by an enzyme Lagging Strand RNA Primer DNA Polymerase 3’ 5’ Okazaki Fragment copyright cmassengale

Joining of Okazaki Fragments The enzyme Ligase joins the Okazaki fragments together to make one strand Lagging Strand Okazaki Fragment 2 DNA ligase Okazaki Fragment 1 5’ 3’ copyright cmassengale

Replication of Strands Replication Fork Point of Origin copyright cmassengale

copyright cmassengale Proofreading New DNA DNA polymerase initially makes about 1 in 10,000 base pairing errors Enzymes proofread and correct these mistakes The new error rate for DNA that has been proofread is 1 in 1 billion base pairing errors copyright cmassengale

copyright cmassengale DNA Damage & Repair Chemicals & ultraviolet radiation damage the DNA in our body cells Cells must continuously repair DAMAGED DNA Excision repair occurs when any of over 50 repair enzymes remove damaged parts of DNA DNA polymerase and DNA ligase replace and bond the new nucleotides together copyright cmassengale

copyright cmassengale Question: What would be the complementary DNA strand for the following DNA sequence? DNA 5’-CGTATG-3’ copyright cmassengale

copyright cmassengale Answer: DNA 5’-CGTATG-3’ DNA 3’-GCATAC-5’ copyright cmassengale

copyright cmassengale