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Bell Ringer for 9/10. Without talking or using the text/your phone: 1. State the difference between cohesion and adhesion. 2. Draw the complete carbon cycle, as best you can, in your notes. Label where you can. You have 5 min. For today. We will revisit your carbon cycle soon Ch. 4 lecture
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Bell Ringer for 9/10 Without talking or using the text/your phone: 1. State the difference between cohesion and adhesion. 2. Draw the complete carbon cycle, as best you can, in your notes. Label where you can. You have 5 min
For today • We will revisit your carbon cycle soon • Ch. 4 lecture • Work time: • Carbon and water cycle diagrams w/ annotations and questions • Properties of water foldable
Ch. 4: Chemistry of Carbon Building Blocks of Life
Why study Carbon? • All of life is built on carbon • Cells • ~72% H2O • ~25% carbon compounds • carbohydrates • lipids • proteins • nucleic acids • ~3% salts • Na, Cl, K…
Chemistry of Life • Organic chemistry is the study of carboncompounds • C atoms are versatile building blocks • 6 valence e-, 2 in 1st shell making it full, 4 in 2nd shell, each available for bonding • 4 stable covalent bonds H C H H H
Hydrocarbons • Combinations of C & H • non-polar • not soluble in H2O • hydrophobic • stable • very little attraction between molecules • a gas at room temperature methane(simplest HC)
Basic Naming Rules of Hydrocarbons • Alkanes • Havesingle bonds • Denoted by suffix “-ane” • Formulas fit a CnH2n+2 rule • Alkenes • Havedouble bonds • Denoted by suffix “-ene” • Formulas fit a CnH2n rule • Alkynes • Havetriple bonds • Denoted by suffix “-yne” • Formulas fit a CnH2n-2 rule
Isomers • Molecules with same molecular formula but different structures (shapes) • different chemical properties • different biological functions 6 carbons 6 carbons 6 carbons
Form affects function • Structural differences create important functional significance • amino acid alanine • L-alanine used in proteins • but not D-alanine • medicines • L-version active • but not D-version • sometimes withtragic results… stereoisomers
Form affects function • Thalidomide • prescribed to pregnant women in 50s & 60s • reduced morning sickness, but… • stereoisomer caused severe birth defects
Diversity of molecules • Substitute other atoms or groups around the carbon • ethane vs. ethanol • H replaced by an hydroxyl group (–OH) • nonpolar vs. polar • gas vs. liquid • biological effects! ethanol (C2H5OH) ethane (C2H6)
Functional groups • Parts of organic molecules that are involved in chemical reactions • give organic molecules distinctive properties hydroxylamino carbonylsulfhydryl carboxylphosphate • Affect reactivity • makes hydrocarbonshydrophilic • increase solubility in water
Viva la difference! • Basic structure of male & female hormones is identical • identical carbon skeleton • attachment of different functional groups • interact with different targets in the body • different effects
Hydroxyl • –OH • organic compounds with OH = alcohols • names typically end in -ol • ethanol
Carbonyl • C=O • O double bonded to C • if C=O at end molecule = aldehyde • if C=O in middle of molecule = ketone
Carboxyl • –COOH • C double bonded to O & single bonded to OH group • compounds with COOH = acids • fatty acids • amino acids
Amino • -NH2 • N attached to 2 H • compounds with NH2 = amines • amino acids • NH2 acts as base • ammonia picks up H+ from solution
Sulfhydryl • –SH • S bonded to H • compounds with SH = thiols • SH groups stabilize the structure of proteins
Phosphate • –PO4 • P bound to 4 O • connects to C through an O • lots of O = lots of negative charge • highly reactive • transfers energy between organic molecules • ATP, GTP, etc.
Macromolecules Building Blocksof Life
Macromolecules • Smaller organic molecules join together to form larger molecules • macromolecules • 4 major classes of macromolecules: • carbohydrates • lipids • proteins • nucleic acids
H2O HO H HO H HO H Polymers • Long molecules built by linking repeating building blocks in a chain • monomers • building blocks • repeated small units • covalent bonds Dehydration synthesis
H2O HO H HO H enzyme HO H How to build a polymer You gotta be open to“bonding! • Synthesis • joins monomers by “taking” H2O out • one monomer donates OH– • other monomer donates H+ • together these form H2O • requires energy & enzymes Dehydration synthesis Condensationreaction
H2O HO H enzyme H HO H HO How to break down a polymer Breaking upis hard to do! • Digestion • use H2O to breakdown polymers • reverse of dehydration synthesis • cleave off one monomer at a time • H2O is split into H+ and OH– • H+ & OH– attach to ends • requires enzymes • releases energy Hydrolysis Digestion
Carbon Carbon exists in the nonliving environment as: • Carbon dioxide (CO2) • Carbonic acid ( HCO3−) • Carbonate rocks (limestone and coral = CaCO3) • Deposits of Fossil fuels • Dead organic matter
Organic Carbon • Hydrocarbons: CH4 • Carbohydrate: CH2O
Inorganic carbon • Carbon Dioxide: CO2 • Calcium Carbonate: CaCO3 Mandale Limestone Quarry
Carbon reservoirs • The atmosphere. • The biosphere (include fresh water systems and non-living organic material, such as soil carbon). • The oceans ( including dissolved inorganic carbon and living and non-living marine biota). • The lithosphere (sediments, Earth core including fossil fuels).
Carbon is released into the atmosphere in several ways • Respiration by plants and animals. • Decay of animal and plant matter. • Combustion of organic material • Production of cement. • The ocean releases CO2 into the atmosphere. • Volcanic eruptions and metamorphism
Carbon is taken from the atmosphere in several ways • Photosynthesis. • The oceans when the seawater becomes cooler, more CO2 dissolve and become carbonic acid. • In the upper ocean areas organisms convert reduced carbon to tissues, or carbonates.
Photosynthesis • CO2 + H2O + sunlight CH2O + O2
Respiration • CH2O + O2 CO2 + H2O + energy
Combustion or Oxidization of hydrocarbon CH4 + 2 O2 CO2 + 2 H2O + energy
Human Impacts on the Carbon Cycle Burning fossil fuels have serious impact on the carbon cycle.
Fossil Fuel 86% of global primary energy consumption is fossil fuels.
Fossil Fuels • Petroleum • Natural Gas • Coal
CO2 Concentration Pre-Industrial value: 280 ppm (600 billion tons) Current value: 395 ppm (850 billion tons) Critical value: 560 ppm (1200 billion tons)