Life depends on chemical reactions'

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• Life depends on chemical reactions.

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• Chemistry involves matter and its energy
  relationships. This was dramatically
  demonstrated on May 6, 1937 at Lakehurst, N.J.,
  as the hydrogen lifted airship Hindenberg
  approached its mooring. The following chemical
  reaction requires only hydrogen, oxygen and some
  activation energy--and produces just water and
  heat!!!

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2H2 O2 --gt 2H2O

• Movie

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Ch. 2 Chemistry

• Definition of Concepts Matter and Energy
• Solid, liquid, gas
• Energy
• Energy
• Stored energy that could do work
• Energy
• Object that can do work

Matter
Potential
Kinetic
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Composition of Matter Atoms and Elements

• Basic Terms
• a unique fundament substance
• Periodic Table of the Elements
• Know H, C, N, O, Na, S, Cl, K, Ca
• Atomic Symbols
• 112 unique to each element
• smallest particle of an element
• Element is composed of atoms

Elements
Atoms
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• Atomic Structure
• central mass with
• Protons positive charged particles
• Neutrons neutral charged particles
• Proton Neutrons most of atoms mass

Nucleus
Electrons

• encircle nucleus in orbitals
• are negatively charged particles
• Atoms are electrically neutral
• are charge imbalanced

Ions
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• Identifying Elements
• Atomic Number
• Equals the number of protons
• Atomic Mass Number
• Sum of the number of proton neutrons in the
  nucleus

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• Isotopes
• Same Atomic Number but have different Mass Number
• Fixed of protons, but differing of neutrons
• Radioisotopes
• Unstable nucleus gives off subatomic particles or
  electromagnetic waves

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• Atomic Weight (Mass)
• The average mass for all isotopes of an element
• Molecular Weight (Mass)
• The sum of all the weights of all the atoms in a
  molecule

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How Matter is Combined Molecules and Mixtures

• Molecules two or more atoms chemically bonded
• O2, O3 (ozone)
• Compounds two or more different atoms chemically
  bonded
• H2O, C6H12O6 (sugar glucose)

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• Mixtures
• Two or more compounds physically intermixed
• Solutions homogenous mixtures usually liquids
• Solvent dissolving medium
• Solute substance in the medium
• heterogeneous and translucent
  mixtures
• heterogeneous mixtures
  with visible chunks

Colloids
Suspensions
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Chemical Bonds

• The Role of Electrons in Chemical Bonding
• Electron Shells
• First shell holds 2 e-
• Second and Third each hold 8 e-
• Valence refers to the of e- in the outmost
  shell
• Rule of Eight
• First shell stable with
• Second and Third shell stable with
• Movie

2 e-
8 e-
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• Periodic Table
• Valence of H, C, N, O, Na, S, Cl, K, Ca
• Their common state in water for H, Na, Cl, K, Ca
• Chemically Inert Elements
• Chemically Active Elements

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• Types of Chemical Bonds
• Ionic Bonds e- transfer between two atoms
• Ions Charge imbalanced atoms
• net negative charge ex.
• net positive charge ex.
• Opposite charges can attract, e- exchanged,
  association (bond) formed
• Crystals Salts
• NaCl
• cation or anion in
  solution that conducts electrical current
• Movie

Anions
Cations
Electrolyte
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• Covalent Bonds e- shared between atoms
• Single Covalent Bonds
• CH4, H2O
• Multiple Covalent Bonds
• O2, H2, N3
• Movie

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• Nonpolar Molecules
• Balanced charges between Atoms
• CO2
• Polar Molecules
• 
  greater attraction for shared e-
• lesser
  attraction for shared e-
• Between atoms there is a difference in charge
  distribution, an unequal sharing of e-, and a
  Dipole (polar molecule) results
• H2O

Electronegativity
Electropositivity
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• Hydrogen Bonds H is electropositive, forms
  bonds with electronegative atoms (O N)
• Hydrogen bonding occurs between water molecules
• How?
• A weak bond with biological implications
• Surface Tension
• High Specific Heat
• High Heat of Vaporization
• Polarity/Solvent Properties
• Reactivity in rxns

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Chemical Reactions

• Chemical Equations
• Reactants substance entering a reaction
• substances that result from
  reaction
• Molecular Formula C6H12O6
• so, C6H12O6 -gt CO2 H20

Products
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• Patterns of Chemical Reactions
• Synthesis (Combination) Reaction
• A B -gt AB APP P -gt APPP
• Anabolic rxn
• Decomposition Reaction
• AB -gt A B APPP -gt APP P
• Catabolic rxn

Dehydration
Hydrolysis
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• Exchange (Displacement) Reaction
• AB C -gt AC B

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• Oxidation Reduction Reactions exchange of e-
  between reactants
• is the loss of an e-
• An e- donor
• is the gain of an e-
• An e- acceptor
• Na Cl -gt Na Cl-
• C6H12O6 6O2 -gt 6CO2 6H20

Oxidation
Reduction
Oxidation
Reduction
Oxidation
Reduction
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• Reversibility of Chemical Reactions
• Most A B ltgt AB
• Irreversible A B -gt C
• Factors Influencing the Rate of Chemical
  Reactions
• Temperature
• Particle Size
• Concentration
• Catalysts increase the rate of a rxn and are not
  consumed

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Biochemistry

• Inorganic Compounds usually do not contain
  Carbon (C)
• Water
• Salts ionic compounds (w/o H or OH-)
• NaCl
• In water, Na Cl- ions

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• Acids and Bases
• release H
• HCl -gt H Cl-
• Strong vs weak acid
• accept H or release OH-
• NAOH -gt Na OH-
• Strong vs weak base
• pH Acid-Base Concentration
• pH Scale is logarithmic
• H

Acids
Bases
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• Neutralization
• Acid Base gt
• Buffers
• NaHCO3
• CO2 H20 lt-gt H2CO3 lt-gt H HCO3
• Carbonic acid-bicarbonate buffer system

salt
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Organic Compounds

• Carbohydrates sugars
• CH2Os C6H12O6 lt-gt 6CO2 6H20
• Monosaccharides
• Glucose (6C or hexose) principle blood sugar
• Fructose (6C) fruit sugar, a monomer in sucrose,
  metabolized into glycogen
• Galactose (6C) a monomer in lactose, used to
  construct Glycolipids
• Ribose (5C or pentose) ring-sugar in Ribonucleic
  acids 2 C has OH group
• Deoxyribose (5C) ring-sugar in Ribonucleic
  acids 2 C has only H group, hence its name!

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• Disaccharide (C6H12O6 )2
• Condensation rxn between 2 monosaccharides
• Glucose Fructose lt-gt Sucrose
• Glu Glu lt-gt Maltose
• Galactose Glu lt-gt Lactose

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• Polysaccharides (C6H12O6 )n
• Polymer of many sugar residues
• Cellulose most abundant organic compound on
  Earth Glu polymer, but bonds not easily broken
  by most animals-gtindigestible
• Starch Glu polymer with some branch chains
• Glycogen Glu polymer and many branched chains
• Cellular fuel, structural, signal molecules

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• Lipids hydrocarbons
• Mostly insoluble in water CxHx and some O
• Neutral Fats energy storage
• Glycerol Fatty acid (3)
• Saturated fat (CH)
• Unsaturated fat (CC)
• Omega-3 fatty acids

Triglycerides
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• Phospholipids
• Modified Triglycerides
• Glycerol 2 Fatty Acids Phosphorus-containing
  group
• Polar molecule of cell membrane
• Cell membrane lipid with one or more covalently
  bonded sugars.
• Cell-Cell recognition markers

Glycolipids
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• Steroids
• 4 interlocking hydrocarbon rings
• Cholesterol
• Hormone synthesis, cell membrane component
• Eicosanoids
• Cell membrane component
• Modified to make Prostaglandins
• blood clotting, inflammation, labor contractions

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• Amino Acids Proteins
• Amino Acids (aa)
• C H C00H NH2 R-group
• 20 amino acids
• Condensation rxn produces a peptide bond betw.
  aas

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• Structural Levels of Proteins
• Primary Level linear sequence of aas
• Secondary Level alpha helix or beta pleated
  sheet maintained by hydrogen bonds
• covalent bonds between aas
  (disulfide bridges)
• Quaternary Level interaction of 2 or more
  tertiary level structures

Tertiary Level
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• Fibrous Proteins structural
• Globular Proteins functional
• Protein Denaturation disruption of bonds in the
  protein sometime irreversible

heat
pH
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• Enzymes and Enzyme Activity
• Biological catalyst
• Increase rxn rate, and are nor consumed in rxn
• Lower activation energy barrier, making more
  favorable for substrate(s) (reactants) to become
  products of the rxn
• Cannot create a rxn, but facilitate what occurs
  naturally
• Active Site on enzyme holds substrate(s) and
  applies a stress that facilitates bond making
  or breaking
• Enzymes catalyze reactions

Anabolic or Catabolic
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• Mechanism of Action of an enzyme is to lower the
  activation energy barrier
• Form an Enzyme-Substrate complex
• Cofactors nonprotein substances required for the
  rxn
• Magnesium (Mg) or Zinc (Zn)
• Coenzymes cofactor that are vitamins
• NAD
• FAD
• Movie 1 and Movie 2

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• Nucleic Acids (DNA RNA) C, H, N, P
• Nucleotides have
• Pentose sugar (5 carbon sugar rings)
• Phosphate group
• Nitrogen containing base
• DNA nucleotides
• Adenine
• Guanine
• Cytosine
• Thymine
• RNA nucleotides the above except
• Uracil and no Thymine

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• Deoxyribonucleic acid
• Genetic material of cells in the nucleus and
  mitochondria
• A double-stranded autoreproducing component of
  chromosomes, the Double helix
• Deoxyribose
• Ribonucleic acid
• Material in the nucleus and cytoplasm
• A single-stranded component of protein synthesis,
  the structures of which are specified by DNA
• Ribose

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• Adenosine Triphosphate (ATP)
• Adenosine nucleotide 3 Phosphate groups
• High-Energy Phosphate transfers
• ATP -gt ADP P-X

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Assignments

• What is the molecular weight (mass) of a glucose
  molecule?
• Predict If the respiration rate increases,
  carbon dioxide is eliminated from the blood.
  What effect does this change have on blood
  hydrogen ion levels?
• Define acid and base, and differentiate between a
  strong acid or base and a weak acid or base.
• Describe the different structural levels of
  proteins. Define enzymes and state their
  functions.
• Some antibiotics act by binding to certain
  essential enzymes in the target bacteria. How
  might these antibiotics influence the chemical
  reactions controlled by the enzyme? What is the
  anticipated effect on bacteria?

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• Return to
• atoms