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Physical Properties • Due to the polar nature of water • Hydrogen bond- weak attraction between hydrogen on adjacent molecules such as water H H O H H O Hydrogen bond Water and it’s importance to Life • Life evolved in water • Water’s unique properties have made life as we know it possible Physical Properties • Heat of vaporization- amount of energy that is released or gained when changing state from liquid to gas or back Physical Properties • High Specific Heat- the amount of heat absorbed or released when water changes temperature by one degree C. ( 1 cal. ) Ice Floats • As a liquid water’s hydrogen bonds continuously break and reform • As a solid four molecules form hydrogen bonds creating crystals with open channels and thus fewer molecules per area. Physical Properties • Water reaches maximum density at 4 degrees C. • Water is a universal solvent due to it’s polar nature Evaluate the importance of the following and explain the property of water responsible. • • • • • Cytoplasm is 98 % water Ice Floats Lake effect temperature moderation Evaporative Cooling Spring-Fall Overturn Most Abundant Chemicals in Life • • • • Carbon Oxygen Hydrogen Nitrogen 96 % • Ca, P, K, S, Na, Cl, Mg > 4 % Carbon is special • Tetrahedral structure- four valence electrons shared • Covalent bonds - stability Carbon is Special • Variations are possible in carbon molecules that provide diversity • Isomers are possible structural- differ in structure same chemical formula geometric-differ in spatial relationship enantiomers-mirror images of each other Condensation Synthesis A + B A B + H2 O A and B could be monosaccharides or amino acids Hydrolysis + H2O + Addition of water breaks the bond Polymers Polymers are repeating units of monomers. They are very important to Biology. They are made or synthesized by the removal of water called CONDENSATION SYNTHESIS They are broken down by the addition of water or HYDROLYSIS Classes of Biomolecules • Carbohydrates- used for energy and structures( building living organisms) • Lipids- used for energy storage, communication and structures • Proteins- used for a variety of life functions • Nucleic Acids-the instructions for building life Carbohydrates • Three common forms – Monosaccharides – Disaccharides – Polysaccharides Carbohydrates • Monosaccharides- single sugars or simple sugars,ex. Glucose ( C6H12O6) • Disaccharides- double sugar, ex. Sucrose • Polysaccharides- polymers of glucose such as: 1. Starch 2. Cellulose 3. Glycogen 4. Chitin Review • What will happen here? AOH + HB = ? And here: CH2OH CH2OH O OH O H OH OH H OH OH OH H2O OH OH Dehydration Synthesis or a Condensation Reaction A + B = AB + H2O CH2OH CH2OH O O O OH OH OH OH H2O OH OH Review • What will happen here? AB + H2O = ? And here: CH2OH CH2OH O H2O O O OH OH OH OH OH OH Hydrolysis or Reaction AB + H2O = AOH + HB Molecules have been HYDROLIZED! CH2OH CH2OH O O OH OH OH OH OH OH OH OH Glucose Glucose has a chemical formula of C6H12O6 CH2OH C OH O H OH C H OH H C C H OH C H FRUCTOSE O CH2OH CH2OH C C HO H C OH H H C OH Disaccharides • Sucrose and Lactose • 2 monosaccharides bonded together CH2OH CH2OH O O O OH OH OH OH OH Alpha or Beta? OH Polysaccharides • 3 or more Monosaccharides bonded together CH2OH CH2OH O CH2OH O OH O O OH OH OH O OH OH OH OH Polysaccharide • • • • Starch-storage in plants Cellulose-structural part of plant cell wall Glycogen- storage in animals, liver Chitin – structural component for arthropods, exoskeleton. Also found in fungi. Polysaccharides – Starch • Plants use it as energy storage • Difficult for humans to break down – Ex. Avoid a high starch diet polysaccharides Glucose monomers Polysaccharides – Cellulose (B 1, 4 linkage) • Long fibers • Up to 15,000 Glucose units per strand • Most abundant biological substance on earth – Ex. Cotton, Trees, Paper • Why is cellulose so strong? • Why can’t humans breakdown cellulose and cows can? Polysaccharides – Glycogen • Animals use it as energy storage • Lots and lots of it in the liver • Forms huge branched storage units which allow for easy break down for energy Other polysaccharides • Chitin – Found in the exoskeleton of insects, and arthropods • Ex. Crabs, lobsters, grasshoppers • Pectin – Found in plant cell walls – Provides rigidity • Heteropolymers – Glycoproteins and peptidoglycans Protein Polymers of amino acids With 20 natural amino acids there are a variety of proteins Amino Acids The building blocks of protein H H H O N -C - C OH R R- there are twenty different R groups possible Alanine Glycine NH2-CH-COOH CH3 NH2-CH2-COOH Peptide bond- is a bond between amino acids a molecule of water is removed Protein Structure 1. Primary- order of the amino acids 2. Secondary- hydrogen bonds cause pleats and helix 3. Tertiary- folds and loops create shape by R Group bonds 4. Quaternary-interaction of several proteins A protein with secondary structure A protein with Tertiary Structure Lipids • Large molecules that do NOT have an affinity for water; not soluble in. • May have hydrophobic-water fearing and hydrophilic-water loving parts. Triglycerides hydrophilic hydrophobic Types of Lipids • Made of hydrocarbons • Triglycerides- fats, waxes, and oils(saturated all single bonds C-C, unsaturated have double C=C bonds • Phospholipids- attached phosphate replaces one of the hydrocarbon tails • Steroids- Ring Forms of Hydrocarbons cholesterol and some hormones Triglycerides • Saturated fats- single bonds make this a solid at room temperature and more difficult to digest. Unsatured Fats • Triglycerides that contain double bonds ( dehydrogenated) are liquids at room temp and more digestable Nucleic Acids • Made of monomers called nucleotides • DNAdeoxyribonucleicacid • RNA- ribonucleic acid • These molecules carry all DNA Basic Composition • DNA is made up of nucleotides • Nucleotides are made of …………...Deoxyribose sugar ……………Phosphate ……………Base bases are guanine,cytosine, thymine and adenine RESPIRATION C A T A B O L I S M SYNTHESIS ATP SYNTHESIS FROM ADP + Pi A N A B O L I S M Free Energy • Ability to do work in the cell or ecosystem. Energy Transfer • • • • ATP formation + G ENDERGONIC Stores energy in phosphate bond • ATP breakdown •- G • EXERGONIC • Releases energy between phosphates Enzyme Characteristics • Lower the activation energy • Speed up the rate of a reaction • Act as catalysts • Are proteins (occasionally RNA) Enzyme Characteristics • Conformation or shape is most important feature ( Lock and Key Hypothesis) • Substrate Specific • Do NOT become part of reaction Enzyme activity. 7 pH Enzyme activity. 7 pH Enzyme activity. 10 Temperature o C Enzyme activity. 10 30 Temperature o C Active site Allosteric site substrate products Cofactors • Non protein helpers for enzyme activity • May bind to active site tightly or loosely • Many are inorganic such as zinc or iron • If organic they are called Coenzymes Allosteric site • Regulatory site other than the active site. Competitive Inhibitor substrate inhibitor Enzyme-Substrate Complex Enzyme Noncompetitive Inhibitor Allosteric Regulation Active site activator Active conformation Inactive form Allosteric site inhibitor Feedback inhibition • Product may cause negative feedback (act to inhibit, disrupt conformation) • Reactants may cause positive feedback ( act to preserve enzyme conformation) Initial Enzyme a substance Enzyme b - feedback Enzyme c End product Prokaryotic Cells • Lack a nucleus • Lack membrane bound organells • Include bacteria and other Monerans Eukaryotic Cells • Have a nucleus • Have membrane bound organells • Plants, Animals, Fungi, and Protists have these cell types Organells Membrane Bound ( endomembrane) Nucleus Endoplasmic reticulum (rough) Endoplasmic reticulum ( smooth ) Golgi apparatus Lysosome Vacuoles Vesicles Peroxisome ( single membrane) Mitochoindria Chloroplasts Non membrane bound organells Nucleolus Microtubules Microfilaments Centrioles Cilia Flagella Nucleus • Chromatin- DNA organized with protein (histone) • Controls Protein Synthesis • Double Membrane with pores may be continious with ER • Nucleolus- made of and synthesizes RNA Endoplasmic Reticulum • Rough ER- contains ribosome for protein synthesis • Smooth ER- lacks ribosomes, synthesis of lipids, metabolism of carbohydrates, detoxification of drugs and poisons Muscle ER- calcium ion transfer ER and protein synthesis and Transport Vesicles • Export Proteins – become enclsed in vesicle of the ER Pinch closed Especially secretory proteins ( glycoproteins ) E R.. Golgi Apparatus • Manufacture, storage shipping , and packaging secretion products • Cis • Trans • Vesicles trans cis Phospholipids are amphipathic have both hydrophobic and hydrophilic portions hydrophilic hydrophobic Membrane Fluidity • Unsaturated hydrocarbons in the phospholipids make it flow laterally • Cholesterol maintains some rigidity at low temperatures and prevents too much fluidity at high Membrane proteins • Integral-penetrate into or through the lipid bilayer • used for transport • Peripheral proteinattach to the surface of the lipid layer • used for- receptors, recognition(carbohy drates attached) Permeablility • What passes through easily • Oxygen • Carbon dioxide • water • What does not pass through easily • ions • proteins • carbohydrates Transport • Passive • Requires no expenditure of ATP • Moves from high to low • Can be facilitativeaided by protein conformation change • Gatted channels • Active • Requires ATP energy • Generally moves from low to high • Gatted channels • Na-K pump • Proton Pumps • Phagocytosis or Pinocytosis Solutions • Homogeneous-same throughout • solvent- what you are dissolving into • solute- what you dissolve solution SOLUTE * * * * SOLVENT * Hypertonic .5M glucose .5M glucose Distilled water 1.5 M glucose Water Balance • Plasmolysis( plasmolyzed) plant cell shrinks or looses water • Flacid -plant cell gains water and looses at same rate • Turgid- Plant cell gains Plasmolysis • Membrane shrinks due to water loss • Restricted to cells with walls • Occurs in a Hypertonic environment Facilitated Diffusion • Proteins make movement of polar molecules, ions, or larger compounds possible by providing a passage. • Often protein changes conformation • NO ATP required • Movement from high to low concentration Active Transport • Sodium Potasium Pump • Proton pumps Membrane Potential • Voltage across a membrane • -50 to-200 millivolts • Electrochemical gradientscombination of ion potential and electric charge difference Gated Channels • Chemical or electrical impulses cause them to change shape-OPEN Na-K Pump • Membrane Potential-voltage difference across a membrane • Chemical Gradient-difference in concentration of solute across a membrane • Electro-chemical Gradientcombination of the above ex. • Na+,K+, Cl-(8.13) Exocytosis and Endocytosis • Phagocytosis- engulf pseudopodia • Pinocytosis- gulps • Receptor mediated pinocytosis Signal Transduction • Binding of extracellular molecule to receptor protein see model on pg. 156 Campbell Cell types determine cycle • Prokaryotes- binary fission circular chromosome attaches to inner membrane. Replication is followed by reattachment at two sites. No spindle fibers • Eukaryotes-have a larger genome and nuclear genetic material must be carried on several chromosomes by specialized structures. Can be Confusing? Chomosomes Chromatids Sister chromatids Homologous chromosomes Centromere Centrosome Centrioles Kinetochore Nonkinetochore Chromosomes chromatid Sister chromatid centromere Chromosome Number is fixed in each species Diploid Number Monoploid (haploid) 2n n 46 in humans 23 in humans Somatic Cells-body cells Gametes-egg, sperm, pollen. Cell Cycle Events in the growth, development and reproduction of the cell. Go cells have stopped dividing or have lost the potential to divide. G1- gap or growth after cell division. Cell grows in size. this stage contains the RESTRICTION point S- synthesis of new DNA from existing template(replication) G2- gap 2 or growth prior to cell division M- mitosis or chromosome division C- cytokinesis or cell division Interphase= G1, S, and G2 Control of Cell Cycle Restriction point- go/no go control during G1 G0 - a non-dividing stage for a cell Growth Factors-compounds which regulate growth and division. Ex.PDGF platelet derived growth factor Density-dependent inhibition- crowding inhibits cell division. Adhesiveness- cells ECM causes them to stick together Metastasis-cells(cancerous) migrate Cell Clock Regulators • Proteins ( enzymes) regulate cell cycle • Produced by internal cell clock genes • Protooncogenes- cause cells to divide • Tumor suppressor genes- prevent cell division Cancer and the Cell Cycle • Normal Cells • Adhesive • Contact inhibition • Cancer cells • Lost adhesiveness • Lost contact inhibition Principles of Heredity • Alternative versions of genes (alleles) account for variations in a trait. • For each character, an organism inherits two alleles, one from each parent. • If alleles differ, then the dominant will be fully expressed over the recessive. • The two alleles segregate (separate) during gamete formation. Crossing over During prophase of meiosis homologous pairs may exchange genetic material. New Genetic Combinations • Recombination during fertilization brings together two sets of genetic instructions • Meiosis-crossing over brings about new combinations • Random genetic mutation can result in random genetic change Electron Carriers NAD+ nicotinamide adenine dinucleotide NAD+ When oxidized NADH +2 H+ When reduced FAD or FADH2 Types of Respiration • Anaerobic-without oxygen 1. Alcoholic fermentaion 2.Acetic Acid fermentaion 3. Lactic Acid fermentaion • Aerobic-with oxygen • ALL OF THESE BEGIN WITH THE ANAEROBIC PROCESS OF GLYCOLYSIS GLYCOLYSIS Glucose is made ready to metabolize by addition of phosphates and then it is broken down into 2- 3 carbon compounds (PYRUVATE) This yields a net gain of 2 ATP ACETYL COA FRORMATION • Pyruvate is converted into a 2 Carbon compound and added to an enzyme • CO2 is released Kreb’s Cycle • Breaks C-H-O bonds • Energy is transferred via carriers to other steps • CO2 released • Some small amount of ATP is produced Electron Transport • Hydrogen Pathway- pumps H ions • Electron Transfer • Chemiosmosis- H ions flow through ATP syntase proteins to make ATP from ADP + P Substrate level phosphorylation • ATP is formed as a direct transfer of electrons from the substrate to as ADP + P ATP Oxidative phosphorylation • Electrons made available in metabolism are transferred to oxygen and ATP is produced in the process. Chemiosmosis Fermentation generates ATP by substrate level phosphorylation. It is anaerobic Three Types: AlcoholicLactic Acid- 2 Ethanol +2CO2+NAD 2NAD+2Lactate Photosynthesis CO2+H2O light CnH2n0n+O2 Light- measured as an absorption spectrum, the wavelengths that are most important are different for different types of autotrophs Light rxn. H2O Dark rxn. CO2 light PS1 NADP H Calvin Calvin Cycle Cycle Thylakoid PS2 Photolysis and Photophosphorylation O2 ATP Stroma CnHnOn Visible Spectrum Reflected Absorbed Absorbed 680-700 Primary acceptor NADP+ + 2H -e NADPH pq Cytochrome complex Photosystem I P700 pc Chl a 700nm LIGHT Photosystem II P680 680nm Photosystem I • Also known as P700receives electrons from those released in PSII to replace photoexcited electrons uses light at far end of the red wavelength • PSI 700 • PSII 680 the II in PSII H2O Photosystem II • P680 • due to an association with different proteins • this system utilizes different wavelengths • causes water to split capturing it’s electron • it then transfers the electron to PSII chlorophyll molecules Noncyclic Electron Flow Water is split (photolysis) and electrons pass continuously from water to NADP+. Primary electron acceptors pass photoexcited electron to the electron transport chain(Pq), (Pc), cytochromes. . Uses both PSI and PSII Generates O2, NADPH, and ATP Cyclic Electron Flow Excited Electrons pass through the electron transport chain from P700 (PS I ) and return to the starting point. Uses only PSI Only ATP is generated 3CO2 RuBP 3ATP Carbon Fixation rubisco Calvin Cycle 6ATP 6ADP 6NADPH 3ADP 6NADP Regeneration RuBP G3P--Glucose Photorespiration CO2 can act as a limiting factor. In cases where there is not sufficient Carbon dioxide plants will combine oxygen with RuBP to form compounds that are broken down into CO2 Adaptations for Photosynthesis • C4 Plants • CAM plants • CO2 is added to PEP phosphophenolpyruvat e • stored in BUNDLE SHEATH CELLS near veins of leaf • example- Corn • in hot dry areas plants must close stomates • CO2 taken in at night is stored as an acid Discovery of DNA 1. Frederick Griffith – Was studying Streptococcus Pneumonia – Smooth vs. Rough Strains – Smooth had a mucous coat and were pathogenic (caused pneumonia) – Rough were non-pathogenic – Conducted an experiment with mice – Found out that the Rough bacteria became transgenic Discovery of DNA 2. Avery, McCarty and MacLeod – What was the genetic material in Griffith’s experiment? – Purified the heat–killed S-bacteria • Into DNA, RNA, and Protein – Mixed each with the R cells to see which one transformed Discovery of DNA 3. Hershey-Chase Experiment – Studied viruses that infect bacterial cells – Bacteriophages – Protein or DNA responsible for take-charge actions of the virus? – Tagged the Protein with radioactive S • Why? – Tagged the DNA with radioactive P • Why? The Structure of DNA: a double helix? • Chargaff’s Nucleic Acid Ratios 1. Measured the base compositions of several species 2. Percentage of each base present • Human DNA 1. A = 30% and T = 29% 2. G = 20% and C = 19% The Structure of DNA: a double helix? • Rosalind Franklin and Maurice Wilkins use XRay diffraction to view structure • Watson and Crick propose a double helix using their X-Ray pictures DNA Double Helix DNA: Three Parts • DNA is made up of nucleotides • Nucleotides are made of – Deoxyribose sugar – Phosphate – Base • Guanine, Cytosine, Thymine and Adenine DNA: The Deoxyribose Sugar DNA: The Phosphate DNA: The Nitrogenous Bases • Purines • Adenine and Guanine • Double Ring Structure • Pyrimidines • Thymine and Cytosine • Single Ring Structure Single Stranded DNA Nucleotides can only be added to the 3’ end of the nucleotide and therefore addition of new nucleotides is always 5’-----> 3’ DNA is anti-parallel!! DNA STRUCTURE How does it know to pair up? • ADENINE ALWAYS PAIRS WITH THYMINE • Two hydrogen bonds • GUANINE ALWAYS PAIRS WITH CYTOSINE • Three hydrogen bonds Why do they pair up? • Double helix had a uniform diameter • Purine + Purine – = too wide • Pyrimidine + Pyrimidine – = too narrow • Purine + Pyrimidine – = fits the x-ray data One last look Why does it twist? DNA Replication Meselson-Stahl demonstrate the Semiconservative Replication of DNA using radioactive nitrogen Why must DNA Replicate? • Species Survival – DNA must replicate BEFORE cell division • Synthesis during Interphase • All genes must be present in the daughter cells Origins of Replication • Sites along DNA that contain specific nucleotides are recognized by specific proteins that initiate process • In eukaryotes there are hundreds of thousands of such points • Form replication bubbles How does DNA Replicate? • • • • • Hydrogen bonds break, forming bubbles Enzymes unwind and unzip Free nucleotides in the nucleus start process of complementary base pairing Nucleotides are fused together by DNA Polymerase only 5’ to 3’ Results in two identical double helixes Replication Steps • DNA helicase enzymes open double strand • DNA uncoils and unzips exposing the DNA template • Primase adds a RNA primer as binding proteins hold strands together • DNA polymerase attaches to template at replication fork • Nucleoside triphosphates add bases pairing A-T and G-C as new strand is added to a 3’ end, primer removed replication3 How does DNA Replicate? How does DNA Replicate? Leading Strand is Continuous • A single RNA primers initiates the addition of nucleotides to the 3’ end of the leading strand Lagging Strand • Must wait for replication fork to open and then add primer • Form Okazaki fragments • RNA is removed only after addition of about 100 to 200 nucleotides • Fragments are joined by a ligase enzyme ( DNA glue) DNA Replication The result • DNA Replication results in TWO double helixes. DNA unwinds and unzips, and new daughter strands form, each complementary to an old parental strand. RNA - Structure • “Ribonucleic Acid” – different from DNA • Always Single Stranded • Ribose Sugar Base Unit • Phosphate group (same in DNA) • Nitrogenous Bases – Cytosine always pairs with Guanine – BUT! Adenine always pairs with URACIL • (different in DNA!!!!!) Four kinds of RNA • Ribosomal RNA • Messenger RNA • Transfer RNA • snRNA ribozyme in spliceosome rRNA • • Ribosomal RNA or rRNA • represents about 70% of cellular RNA • joins with Ribosomal proteins to make the cellular organelle: RIBOSOMES FUNCTION – As a manufactured ribosome, supplies a location for tRNA to join with mRNA to synthesize a protein mRNA 2. Messenger RNA or mRNA • • • • • represents about 10% of cellular RNA contains the sequence of bases coding for a particular amino acid sequence in a polypeptide chain removal of non-coding, internal sequences (introns) modification of the 5' base (cap) addition of adenines to 3' end (poly A tail) FUNCTION – reads the DNA code (base sequence) and becomes a copy that is read at the ribosome to make a protein hn RNA • Pre-mRNA contains intronsnon-coding regions as well as exons-coding regions Processing mRNA • Deletion of introns • Join exons • Add cap ( GTP) and poly A tail RNA splicing • Spliceosome-several snurps • snRNPs small nuclear Ribonucleoproteins-splicing enzyme( cuts and glues) Transcription • • DNA unzips at the locus of the gene being coded mRNA makes a copy of the gene • • Then… mRNA is enzymatically modified – A cap and a tail are added • it then leaves the nucleus and finds a ribosome (composed of rRNA and protein) tRNA • • • • • Transfer RNA or tRNA represents about 20% of cellular RNA each tRNA molecule is specific for one amino acid there is an enzyme for each amino acid which recognizes the amino acid and its specific tRNA and joins the two together the specific joining of tRNA to amino acid is the only place where the “genetic code" applies FUNCTION – Pairs with Amino Acids and delivers them to ribosomes at the right time to synthesize a protein Protein Synthesis • Why should cells do this? – Cells would not be able to grow and change without proteins. – Proteins are found everywhere: • As enzymes, cell membranes, muscles, heart, blood… • What happens when proteins are not made correctly or not made at all? – Ex. Cystic Fibrosis • What part of DNA holds the code for the protein? PROTEIN SYNTHESIS Everyone is involved • Transcription DNA, mRNA • Translation mRNA, rRNA and tRNA Pre-Translation • mRNA binds to the ribosome • Meanwhile, tRNAs are attaching to their amino acids using tRNA Transferase • Free tRNAs, with their amino acids attached, circulate in the cytoplasm and match up with the triplet codes in the mRNA Translation Initiation • The first tRNA enters the ribosome at the A site • The second tRNA enters the ribosome (at the P site) and the amino acids are bonded together = PEPTIDE BOND Elongation • Both tRNAs shift in one direction and make room for the next tRNA to enter the ribosome • this pattern continues until the protein is complete Quick Definitions A-site – aminoacyl-tRNA binding site P-site – peptidyl-tRNA binding site Triplet code – DNA Codon – RNA Anti-codon - tRNA Introns – removed from initial mRNA Exons – bonded together to make the finished mRNA product for translation Polyribosomes – more than one ribosome reading the mRNA at one time Codons and anti-codons Triplet code on DNA TAC mRNA copies it: CODON AUG tRNA carries the ANTICODON UAC The Genetic code reads the codon AUG, the amino acid: Methionine • • • • • 45 different anti-codons exist AUG is always the initiation codon GTP supplies energy needed to synthesize protein initiator tRNA always carries Methionine first! Initiation factors - proteins that bring all parts together (mRNA, small subunit, large subunit, and tRNAs) Genetic Code • Interprets what the DNA triplet code reads • Is written in both DNA base language A, G, C, T or RNA base language A, G, C, U • Determines the order for Amino Acids • Is universal within all species • Reads the same as the anti-codon (on tRNA) except T is now U Genetic Code Gene Regulation Control of gene expression occurs at four levels in human cells: Transcription and posttranscription control (nucleus) Translation and posttranslation control (cytoplasm) • Various cells express different genes • Genes can be turned on or off • Genes respond to activity outside of the cell • Control of transcription is most important regulatory mechanism (binding factors and enhancers) Presence of TF determines specialization DNA Technology • Biotechnology or genetic engineering – the use of natural biological systems to produce a product desired by human beings Examples include: • • • • • • Gene Cloning DNA Amplification Transgenic Organisms Gene Therapy Chromosome Mapping and Sequencing Gene Cloning Gene Cloning • Recombinant DNA – DNA from two different sources (human and E. coli) • Plasmid – circular DNA used to transport the gene into the organism • Enzymes needed – Restriction and Ligase • Host cell – usually bacteria, wall must become competent in order for the bacteria to uptake the plasmid • Restriction enzyme cleaves DNA and allows for DNA fragment to insert at the sticky ends • Vector – method of transporting a gene (virus, plasmid) pVIB lux genes 2 genes to produce LUCIFERASE Aldehyde (energy source) synthesis several genes Regulatory genes to turn of and on DNA Amplification Polymerase Chain Reaction – PCR • Used to make multiple copies of the same gene • Copies can be examined to see if they match any other sources • Prevents constant extraction from the organism and better results Other Technologies • Recombinant DNA - gene splicing • Transgenic organism- an organism that contains another organism’s DNA Transgenic Organisms • Transgenic – possessing gene(s) from another organism • Gene Pharming – Using transgenic farm animals to produce pharmaceuticals ex. CF, cancer, blood clots • Genetically altering crops to be resistant to insects and produce larger http://biology.about.com/science/biology/gi/dynamic/offsite.htm?site=http://abcnews.go.co m/sections/science/DailyNews/gmcorn%5Fbutterflies000821.html • Suicide Genes • Insulin Gene Therapy • Delivering the defective gene to the cells that need it to produce a protein • Familial hypercholesteremia • SCID – severe combined immunodeficiency syndrome (missing maturation enzyme for T and B cells) Chromosome Mapping • 100,000 human genes • RFLPs – Restriction Fragment Length Polymorphisms – used to probe a region of DNA – visible under a microscope • Restriction enzymes – sequence AA • Specific base digestion – CF LAB Human Genome Project • HGP – due for completion in 2002 • Already sequenced the Fruit Fly and E. Coli Gene Therapy • Delivering the defective gene to the cells that need it to produce a protein • Cystic Fibrosis • Vector – method of transporting a gene (virus, plasmid) – Mechanical - usually a laboratory tool used (inoculating loop) – Biological - part or whole of an organism (bacteria) Chromosome Mapping • 30,000 human genes • RFLPs – Restriction Fragment Length Polymorphisms – used to tag a region of DNA – visible under a microscope • Restriction enzymes – sequence AA • Specific base digestion Sanger Method of DNA Sequencing 1. Heat DNA Strands until they separate 2. Add nucleotides and DNA Polymerase 3. Add Dedeoxynucleotides (A, T, G, and C) at different time periods to stop replication 4. Place fragments in to Gel Electrophoresis 5. Allow to migrate and read the Base Sequence Electrophoresis Human Genome Project • HGP – due for completion in 2002 • Already sequenced the Fruit Fly and E. Coli • The ultimate goal of HGP is to associate human traits and inherited diseases with particular genes. • It promises to revolutionize both therapeutic and preventive medicine techniques for many human diseases. Human Genome Project • Genome - the complete collection of an organism's genetic material. • The human genome is composed of an estimated 30,000 • A single human chromosome may contain more than 250 million DNA base pairs, and it is estimated that the entire human genome consists of about 3 billion base pairs. DNA Fingerprinting • Treat suspects’ blood with the same restriction enzyme • Place sample in Gel Electrophoresis • Allow samples to migrate • Compare the suspects with the blood found at the crime scene • Used in Criminal Trials: OJ Simpson – OJ – DNA was an exact match yet he was found not guilty?