The Chemistry of Life

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The Chemistry of Life
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Organic Chemistry

• ORGANIC means comes from and found in living
  things
• All organic compounds contain both Carbon and
  Hydrogen together
• Inorganic Doesnt contain both C and H
• Practice Organic or Inorganic???
• H2O ___________ (water)
• NaCl ___________ (salt)
• C6H12O6 ___________ (sugar/glucose)
• CH4 ______________ (methane)
• CO2 _____________ (carbon dioxide)
• O2 ______________ (oxygen)

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Macromolecules

• Means Giant molecules
• Formed by polymerization
• Small things (MONOMERS) join together to make
  large things (POLYMERS)
• EX. monomer monomer monomer polymer
• Four (4) types of Organic Macromolecules
• Carbohydrates
• Lipids
• Proteins
• Nucleic Acids
• VIDEO (310) http//www.brainpop.com/science/matt
  erandchemistry/bodychemistry/

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Carbohydrates

• Elements present Carbon, Hydrogen, Oxygen
• Building Blocks (and Digestive End products)
• Monosaccharides or Simple Sugars
• Example glucose (Formula C6H12O6 )
• Are found in both simple (sugars) and complex
  forms (starches)
• Function
• Main Energy source

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Molecular Structure of Carbs

• 1 Ring MONOsaccharide
• BUILDING BLOCKS of complex sugars
• Ex. Glucose AND fructose
• --------------------------------------------------
  --------
• 2 Rings DIsaccharide
• Ex. lactose, maltose, and sucrose
• --------------------------------------------------
  --------
• 3 or more Rings POLYsaccharide
• Ex. Starch, cellulose, glycogen, chitin

Polysaccharide
Glucose
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Making or Breaking Polymers

• DEHYDRATION SYNTHESIS
• Synthesis building/joining
• Monosaccharides ARE HOOKED TOGETHER BY LOSING A
  WATER MOLECULE TO FORM DI AND POLYSACCS.

• HYDROLYSIS
• Hydrolysis digestion/breaking up
• Polysaccharides AND Disacchararides BREAK APART
  BY ADDING WATER MOLECULES.

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Lipids

• Elements present Carbon, Hydrogen, Oxygen
• Building Blocks (and Digestive End products)
• 3 Fatty acids
• 1 glycerol molecule
• Examples
• Fats, oils, waxes
• Functions
• protection and insulation
• Parts of CELL membranes
• Chemical messengers (hormones)

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Types of Lipids

• Unsaturated Fat
• LIQUID at room temp (ex. Olive oil)
• may lower cholesterol levels

• Saturated Fat
• SOLID at room temp (ex. Butter)
• may lead to heart disease or hardening of the
  arteries

Bad for you Good for you
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Proteins

• Elements present
• Carbon, Hydrogen, Oxygen, and Nitrogen
• Building blocks (and Digestive End products)
• Amino Acids
• Amino acids are linked in any order and in any
  number to make endless numbers of proteins!
• Proteins are formed at the ribosomes of a cell
  and held together by peptide bonds.
• The shape determines the function

Amino acid
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Function and (examples) of proteins

• growth and repair
• transport (hemoglobin)
• form bone and muscle (collagen)
• sends signals (hormones-insulin)
• Defense (makes antibodies)
• Control rates of reactions (enzymes)

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Nucleic Acids

• Elements present
• Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus
• Basic Building Blocks
• NUCLEOTIDES
• Lets look closer at one nucleotide
• Nucleotides have 3 parts
• Phosphate
• Ribose sugar
• Nitrogen Base (1 of 4)

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• Each nucleotide is connected across to another
  nucleotide
• Each nucleotide is also connected to another
  above and below.
• This forms the Double-helix molecule

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• Types of Nucleic Acids
• DNA (Deoxy-ribo-Nucleic-Acid)
• RNA (Ribo-Nucleic-Acid
• Functions
• Store and transmit GENETIC information

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Group activity

• Create a graphic organizer, using the template
  below as a starting point, in order to organize
  important information regarding the four major
  organic molecules.
• Include (minimally)
• What is the molecule made of?
• What is its function(s)?
• Examples (general or specific)?

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Acids and Bases

• used for different functions in body (such as
  digestion).
• pH is different in different parts of body, like
  acid (pH 3) in stomach and basic (pH 8) in small
  intestines

VIDEO (349) http//www.brainpop.com/science/matt
erandchemistry/phscale/
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Characteristics of Acids

• Any compound that GIVES OFF H ions in solution
• Ex. HCl H and Cl-
• Traits
• Sour taste
• pH value less than 6.9
• Strong acids 1-3
• Common acids
• Juices, vinegar, HCl

Add water
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Characteristics of Bases

• Any compound that GIVES OFF OH- ions in solution
• Ex. NaOH Na and OH-
• Traits
• Slippery
• PH greater than 7.1
• Strong base pH 11 - 14
• Common Bases
• Soaps, detergents, ammonia

Add water
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pH scale

• measures the strengths of acids and bases.
• pH 0-6.9 acid
• pH 7.1-14 base
• pH 7 neutral (water).

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Chemical Indicators - Are used to test for
certain substances

• Lugols solution (iodine)
• Tests for starch
• Yellow no starch
• Blue/Black starch
• Benedicts solution
• Tests for monosacchardies
• (ie. Glucose)
• Blue no glucose
• A diff. color glucose

Positive Test
Negative Test
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• 3. Litmus paper
• Tests for Acids or bases
• Red change acidic
• Blue change basic
• 4. Bromothymol blue
• Test for carbon dioxide
• Blue basic (gt7.6 pH )
• Green neutral (7 pH)
• Yellow acidic (lt 6.0 pH )

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Lets Practice pH activity

• http//www.bgfl.org/bgfl/custom/resources_ftp/clie
  nt_ftp/ks3/science/acids/

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Enzymes
Click for Discovery channel video

• The biological catalyst of life

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Enzymes. are protein substances that are
necessary for

• The chemical reactions that occur in your body
• Ex. Pepsin (enzyme) breaks protein down in the
  stomach.
• Help to release energy in the form of ATP
  (adenine tri-phosphate) to the cells

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Enzyme Vocabulary

• Enzymes end in ase
• Maltase binds to maltose
• Lactase binds to lactose
• Lipase breaks down fat
• Amylase is found in saliva
• Catalyst
• Substance that affects the rate of a chemical
  reaction WITHOUT BEING ALTERED
• Because it is not altered, can do same thing
  over, and, over, and, over, and over.
• Enzymes are ORGANIC CATALYSTS

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Enzyme Vocabulary

• Substrate
• The substance upon which the enzyme reacts
• Active site
• Site where enzyme binds to substrate
• Denature
• When enzymes shape is altered due to
• high temp
• strong acids or bases

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How Do Enzymes Work?

• The enzyme has an active site which has a on its
  surface which has a very specific shape.
• The enzyme and the substrate (what enzymes acts
  upon) temporarily join together forming the
  enzyme substrate complex.

DEMO
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Importance of Enzyme Shape

• Enzymes have specific shapes
• This means enzymes are specific to their
  substrate
• They will only attach to a substrate that fits
  their shape
• If shape of enzyme is denatured, will it be able
  to bind to its substrate?
• NO!
• Two things can cause denaturing
• Temperature
• pH

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Enzyme-Substrate Complex

• Formed when enzyme binds to substrate
• Very specific

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Lock and Key Model

• Enzyme-substrate complex often compared to a
  lock and key.
• Active site on enzyme can only FIT or bind
  to a specific substrate
• Example Amylase will bind to starch, but not
  cellulose

• http//www.youtube.com/watch?vPILzvT3spCQfeature
  fvwrel

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What factors influence Enzyme Action?

• Remember, enzymes speed up reactions
• What can affect the rate at which enzymes
  perform?
• Its shape!
• Denaturing affects rate
• The amount of enzyme and substrate!

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Temperature - Enzyme shape and reaction rate

• Enzymes have a specific temperature range at
  which they work best
• EX. Human enzymes work best at 37C
• Temps not in the optimal range will cause enzymes
  to denature
• Shape is altered, so reaction rates are SLOWED or
  stopped altogether
• Reaction rates will DROP dramatically depending
  on how much denaturing of enzyme

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Temperature vs. Reaction Rate
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pH - Enzyme shape and reaction rate

• Enzymes have a specific pH range at which they
  work best
• EX. Most enzymes work best at pH 7
• Where in the body would enzymes be optimal at a
  low (acidic) pH? Why?
• In stomach, this is because stomach acid has a
  low pH
• pH not in the optimal range will cause enzymes to
  denature
• Shape is altered, so reaction rates are SLOWED or
  stopped altogether
• Reaction rates will DROP dramatically depending
  on how much denaturing of enzyme.

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pH vs. Reaction Rate
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Concentration - Enzyme amount and reaction rate

• Enzyme rate also depends on the amount of enzyme
  and substrate
• Little enzyme, lots of substrate
• Slower rates
• How can we speed up the rate?
• Add more enzyme until max. rate achieved.

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Substrate Concentration vs. Reaction Rate