logging in or signing up DNA The Molecule of Life sasha2008 Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 797 Category: Education License: All Rights Reserved Like it (1) Dislike it (0) Added: February 17, 2009 This Presentation is Public Favorites: 3 Presentation Description No description available. Comments Posting comment... By: raassi (24 month(s) ago) am a novice in this field. find most of your presentations easy to understand. Mind mailing a copy to me at raassi@yahoo.com Saving..... Post Reply Close Saving..... Edit Comment Close By: raassi (24 month(s) ago) am a novice in this field. find most of your presentations easy to understand. Mind mailing a copy to me at raassi@yahoo.com Saving..... Post Reply Close Saving..... Edit Comment Close By: neelnikunj (25 month(s) ago) Beautiful presentation for the student. I would be oblige if you will e-mail this to me.-Nikunj. e-mail: neelnikunj@yahoo.com Saving..... Post Reply Close Saving..... Edit Comment Close By: ardhiwirayuda (27 month(s) ago) Wonderful. Would you email this ti me? TQ Saving..... Post Reply Close Saving..... Edit Comment Close By: abbmdfacc (31 month(s) ago) I would much appreciate a copy of this presentation for educational purposes. If possible, could you please send me a copy to abb2006@med.cornell.edu Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Slide 1: DNA: The Molecule of Life Salwa Hassan Teama Slide 2: What is a DNA?? Slide 3: Deoxyribonucleic Acid (DNA), the genetic material of all cellular organisms and most viruses, the gigantic molecule which is used to encode genetic information for all life on Earth. Slide 4: Within cells, DNA is organized into structures called chromosomes. Eukaryotic organisms (animals, plants, fungi, and protists) store their DNA inside the cell nucleus, while in prokaryotes (bacteria and archae) it is found in the cell's cytoplasm. Slide 5: In normal human cell DNA contained in the nucleus, arranged in 23 pairs of chromosomes. Slide 6: 22 pairs of chromosomes (autosomes); the 23 chromosome pair determines the sex of individual and is composed of either two (x) chromosomes (female) or an (x) and (y) chromosome (male). General Structure of Nucleic Acid : General Structure of Nucleic Acid DNA is a long chain polymers of small compound called nucleotides. The Building Blocks of Nucleic Acids : The Building Blocks of Nucleic Acids Each nucleotide is composed of a base; sugar (deoxyribose) and a phosphate group. The phosphate joins the sugars in a DNA chain through their 5` and 3` hydroxyl group by phosphodiester bonds. Chemical Nature of Polynucleotides : Chemical Nature of Polynucleotides There are four different types of nucleotides found in DNA, differing only in the nitrogenous base: A is for adenine; G is for guanine; C is for cytosine and T is for thymine. The bases pair in a specific way: Adenine A with thymine T (two hydrogen bonds) and guanine G with cytosine C (three hydrogen bonds). Slide 10: These bases are classified based on their chemical structures into two groups: adenine and guanine are double ringed structure termed purine , thymine and cytosine are single ring structures termed pyrimidine. : The structure of DNA was described by British Scientists Watson and Crick based on chemical and physical data that had been gathered in other laboratories, primarily x ray diffraction data collected by Rosalind Franklin and Maurice Wilkins. Slide 13: James D. Watson Francis Crick Rosalind Franklin Maurice Wilkins The Double Helix : The Double Helix long double helix shaped with its sugar phosphate backbone on the outside and its bases on inside; the two strand of helix run in opposite direction and are anti-parallel to each other. The DNA double helix is stabilized by hydrogen bonds between the bases. Source, Cold Spring Harbor Laboratory Archives Slide 15: The double helix often linked to a twisted ladder. The curving sides of the ladder represent the sugar-phosphate backbone of the two DNA strands; the rungs are the base pairs. The spacing between base pairs is 3.32A ?, and the overall helix repeat distance is about 33.2 A ?, meaning that there are about 10 bp per turn of the helix. www.mariemontschools.org/.../dna_molecule The Double Helix : The Double Helix The strands are antiparallel. If one has 5` 3` polarity from top to bottom, the other must have 3 ` 5` polarity from top to bottom. Chargaff's rules : Chargaff's rules Within the structure of DNA, the number of thymine is always equal to the number of adenine and the number of cytosine is always equal to guanine. DNA Replication : DNA Replication DNA Replication: The DNA (all gene duplication; the transfer the genetic information from a parent to a daughter cell ; the DNA base sequence are precisely copied). Semiconservative replication describes the method by which DNA is replicated in all known cells. This method of replication was one of three proposed models of DNA replication: Semiconservative ,Conservative replication ,Dispersive replication Semiconservative replication would produce two copies that each contained one of the original strands and one entirely new strand. Slide 19: Conservative replication would leave the two original template DNA strands together in a double helix and would produce a copy composed of two new strands containing all of the new DNA base pairs. Slide 20: Dispersive replication would produce two copies of the DNA, both containing distinct regions of DNA composed of either both original strands or both new strands. Variety of DNA Structures : Variety of DNA Structures A Form B Form Z Form Variety of DNA Structures : Variety of DNA Structures B DNA, the most dominant form, the base pairs are stacked 0.34 nm apart, with 10bp/turn of the right handed double helix and a diameter of approx, 2nm. Slide 23: A DNA, like B DNA, righthanded helix, however, A DNA exhibits a larger diameter (2.6nm), with 11 bases/turn of the helix and bases are stacked closer in the helix (0.25nm apart). B and A DNA form reveals the presence of a major groove and a minor groove. These grooves particularly the minor groove contain many water that interact with the amino and keto groups of the bases. In a solution with higher salt concentrations or with alcohol added, the DNA structure may change to an A form. : In a solution with higher salt concentrations or with alcohol added, the DNA structure may change to an A form. Slide 25: Z DNA, its bases seem to zigzag. Z DNA is left-handed. One turn spans 4.6 nm, comprising 12 base pairs. The DNA molecule with alternating G-C sequences in alcohol or high salt solution tends to have such structure. DNA Denaturation : DNA Denaturation When a DNA solution is heated enough, the noncovalent forces that hold the two strands together weaken and finally break and the two strand come apart. Slide 27: Melting Temperature; the temperature at which the DNA strands are half denatured. The GC content of a DNA has a significant effect on its Tm. The higher a DNA`s GC content, the higher its Tm. Slide 29: Denaturation is a reversible process. The two single complementary strands can be made to renaturate or anneal into the native double stranded molecule by adjusting the temperature or the salt concentration. Mitochondrial DNA : Mitochondrial DNA Mitochondrial DNA contains 37 genes, all of which are essential for normal mitochondrial function. Thirteen of these genes provide instructions for making enzymes involved in oxidative phosphorylation. Oxidative phosphorylation is a process that uses oxygen and simple sugars to create adenosine triphosphate (ATP), the cell's main energy source. The remaining genes provide instructions for making molecules called transfer RNAs (tRNAs) and ribosomal RNAs (rRNAs). Mitochondrial genes are among the estimated 20,000 to 25,000 total genes in the human genome. Recombinant DNA : Recombinant DNA Recombinant DNA is DNA that has been artificially created for purposes of genetic engineering. Function of DNA : Function of DNA Storage of genetic information Transmission of genetic information DNA Damage : DNA Damage DNA damage can result from spontaneous alteration of the DNA molecule or from the interaction of numerous chemical and physical agents with the structural DNA molecule. Spontaneous lesions can occur during normal cellular processes, such as, DNA replication, DNA repair, or gene rearrangement., or through chemical alteration of the DNA molecule itself as a result of hydrolysis, oxidation or methylation. The various form of spontaneous and induced DNA damage can give rise to different types of mutation. DNA Repair : DNA Repair The cellular DNA is continuously subjected to structural damage through the action of endogenous or environmental mutagens. In absence of efficient repair mechanisms. Stable mutations can be introduced into DNA during the process of replication at damaged sites within the DNA. Mammalian cells possess several distinct DNA repair mechanisms including: Enzymatic reversal repair, nucleotide excision repair and postreplication repair. DNA uses in Technology : DNA uses in Technology Genetic engineering Forensic science Bioinformatics DNA nanotechnology …….. Slide 36: Thank you You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
DNA The Molecule of Life sasha2008 Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 797 Category: Education License: All Rights Reserved Like it (1) Dislike it (0) Added: February 17, 2009 This Presentation is Public Favorites: 3 Presentation Description No description available. Comments Posting comment... By: raassi (24 month(s) ago) am a novice in this field. find most of your presentations easy to understand. Mind mailing a copy to me at raassi@yahoo.com Saving..... Post Reply Close Saving..... Edit Comment Close By: raassi (24 month(s) ago) am a novice in this field. find most of your presentations easy to understand. Mind mailing a copy to me at raassi@yahoo.com Saving..... Post Reply Close Saving..... Edit Comment Close By: neelnikunj (25 month(s) ago) Beautiful presentation for the student. I would be oblige if you will e-mail this to me.-Nikunj. e-mail: neelnikunj@yahoo.com Saving..... Post Reply Close Saving..... Edit Comment Close By: ardhiwirayuda (27 month(s) ago) Wonderful. Would you email this ti me? TQ Saving..... Post Reply Close Saving..... Edit Comment Close By: abbmdfacc (31 month(s) ago) I would much appreciate a copy of this presentation for educational purposes. If possible, could you please send me a copy to abb2006@med.cornell.edu Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Slide 1: DNA: The Molecule of Life Salwa Hassan Teama Slide 2: What is a DNA?? Slide 3: Deoxyribonucleic Acid (DNA), the genetic material of all cellular organisms and most viruses, the gigantic molecule which is used to encode genetic information for all life on Earth. Slide 4: Within cells, DNA is organized into structures called chromosomes. Eukaryotic organisms (animals, plants, fungi, and protists) store their DNA inside the cell nucleus, while in prokaryotes (bacteria and archae) it is found in the cell's cytoplasm. Slide 5: In normal human cell DNA contained in the nucleus, arranged in 23 pairs of chromosomes. Slide 6: 22 pairs of chromosomes (autosomes); the 23 chromosome pair determines the sex of individual and is composed of either two (x) chromosomes (female) or an (x) and (y) chromosome (male). General Structure of Nucleic Acid : General Structure of Nucleic Acid DNA is a long chain polymers of small compound called nucleotides. The Building Blocks of Nucleic Acids : The Building Blocks of Nucleic Acids Each nucleotide is composed of a base; sugar (deoxyribose) and a phosphate group. The phosphate joins the sugars in a DNA chain through their 5` and 3` hydroxyl group by phosphodiester bonds. Chemical Nature of Polynucleotides : Chemical Nature of Polynucleotides There are four different types of nucleotides found in DNA, differing only in the nitrogenous base: A is for adenine; G is for guanine; C is for cytosine and T is for thymine. The bases pair in a specific way: Adenine A with thymine T (two hydrogen bonds) and guanine G with cytosine C (three hydrogen bonds). Slide 10: These bases are classified based on their chemical structures into two groups: adenine and guanine are double ringed structure termed purine , thymine and cytosine are single ring structures termed pyrimidine. : The structure of DNA was described by British Scientists Watson and Crick based on chemical and physical data that had been gathered in other laboratories, primarily x ray diffraction data collected by Rosalind Franklin and Maurice Wilkins. Slide 13: James D. Watson Francis Crick Rosalind Franklin Maurice Wilkins The Double Helix : The Double Helix long double helix shaped with its sugar phosphate backbone on the outside and its bases on inside; the two strand of helix run in opposite direction and are anti-parallel to each other. The DNA double helix is stabilized by hydrogen bonds between the bases. Source, Cold Spring Harbor Laboratory Archives Slide 15: The double helix often linked to a twisted ladder. The curving sides of the ladder represent the sugar-phosphate backbone of the two DNA strands; the rungs are the base pairs. The spacing between base pairs is 3.32A ?, and the overall helix repeat distance is about 33.2 A ?, meaning that there are about 10 bp per turn of the helix. www.mariemontschools.org/.../dna_molecule The Double Helix : The Double Helix The strands are antiparallel. If one has 5` 3` polarity from top to bottom, the other must have 3 ` 5` polarity from top to bottom. Chargaff's rules : Chargaff's rules Within the structure of DNA, the number of thymine is always equal to the number of adenine and the number of cytosine is always equal to guanine. DNA Replication : DNA Replication DNA Replication: The DNA (all gene duplication; the transfer the genetic information from a parent to a daughter cell ; the DNA base sequence are precisely copied). Semiconservative replication describes the method by which DNA is replicated in all known cells. This method of replication was one of three proposed models of DNA replication: Semiconservative ,Conservative replication ,Dispersive replication Semiconservative replication would produce two copies that each contained one of the original strands and one entirely new strand. Slide 19: Conservative replication would leave the two original template DNA strands together in a double helix and would produce a copy composed of two new strands containing all of the new DNA base pairs. Slide 20: Dispersive replication would produce two copies of the DNA, both containing distinct regions of DNA composed of either both original strands or both new strands. Variety of DNA Structures : Variety of DNA Structures A Form B Form Z Form Variety of DNA Structures : Variety of DNA Structures B DNA, the most dominant form, the base pairs are stacked 0.34 nm apart, with 10bp/turn of the right handed double helix and a diameter of approx, 2nm. Slide 23: A DNA, like B DNA, righthanded helix, however, A DNA exhibits a larger diameter (2.6nm), with 11 bases/turn of the helix and bases are stacked closer in the helix (0.25nm apart). B and A DNA form reveals the presence of a major groove and a minor groove. These grooves particularly the minor groove contain many water that interact with the amino and keto groups of the bases. In a solution with higher salt concentrations or with alcohol added, the DNA structure may change to an A form. : In a solution with higher salt concentrations or with alcohol added, the DNA structure may change to an A form. Slide 25: Z DNA, its bases seem to zigzag. Z DNA is left-handed. One turn spans 4.6 nm, comprising 12 base pairs. The DNA molecule with alternating G-C sequences in alcohol or high salt solution tends to have such structure. DNA Denaturation : DNA Denaturation When a DNA solution is heated enough, the noncovalent forces that hold the two strands together weaken and finally break and the two strand come apart. Slide 27: Melting Temperature; the temperature at which the DNA strands are half denatured. The GC content of a DNA has a significant effect on its Tm. The higher a DNA`s GC content, the higher its Tm. Slide 29: Denaturation is a reversible process. The two single complementary strands can be made to renaturate or anneal into the native double stranded molecule by adjusting the temperature or the salt concentration. Mitochondrial DNA : Mitochondrial DNA Mitochondrial DNA contains 37 genes, all of which are essential for normal mitochondrial function. Thirteen of these genes provide instructions for making enzymes involved in oxidative phosphorylation. Oxidative phosphorylation is a process that uses oxygen and simple sugars to create adenosine triphosphate (ATP), the cell's main energy source. The remaining genes provide instructions for making molecules called transfer RNAs (tRNAs) and ribosomal RNAs (rRNAs). Mitochondrial genes are among the estimated 20,000 to 25,000 total genes in the human genome. Recombinant DNA : Recombinant DNA Recombinant DNA is DNA that has been artificially created for purposes of genetic engineering. Function of DNA : Function of DNA Storage of genetic information Transmission of genetic information DNA Damage : DNA Damage DNA damage can result from spontaneous alteration of the DNA molecule or from the interaction of numerous chemical and physical agents with the structural DNA molecule. Spontaneous lesions can occur during normal cellular processes, such as, DNA replication, DNA repair, or gene rearrangement., or through chemical alteration of the DNA molecule itself as a result of hydrolysis, oxidation or methylation. The various form of spontaneous and induced DNA damage can give rise to different types of mutation. DNA Repair : DNA Repair The cellular DNA is continuously subjected to structural damage through the action of endogenous or environmental mutagens. In absence of efficient repair mechanisms. Stable mutations can be introduced into DNA during the process of replication at damaged sites within the DNA. Mammalian cells possess several distinct DNA repair mechanisms including: Enzymatic reversal repair, nucleotide excision repair and postreplication repair. DNA uses in Technology : DNA uses in Technology Genetic engineering Forensic science Bioinformatics DNA nanotechnology …….. Slide 36: Thank you