The Big Four

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The Big Four
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Are you what you eat?
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1. The important Characteristics of Carbon

• Forms 4 covalent bonds
• Forms double and triple bonds
• Forms long chains and rings
• Can bind with many other elements
• Even electron distribution (nonpolar molecules)

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2. Macromolecules, Monomers and Polymers(Hint
think of the meaning of the prefixes)
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What do these words mean?
Micro
MACRO
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What does Mono mean?
1
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"Poly"
Polygons
Polyester
Polygamy
Means...
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2. Macromolecules, Monomers and Polymers

• Polymer Smaller organic molecules join into
  long chains.
• Monomer the individual unit that builds up
  polymers
• Macromolecules Very large molecules

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3. Dehydration synthesis and Hydrolysis

• These two terms refer to the processes that forms
  monomers and polymers
• Dehydration synthesis A reaction that removes
  molecules of water to form polymers from monomers
• Hydrolysis The reaction that adds water to
  polymers to separate them to their individual
  monomers.
• (http//nhscience.lonestar.edu/biol/dehydrat/dehyd
  rat.html or http//www.youtube.com/watch?vUyDnn
  D3fMaU )

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• Isomers
• Molecules that have the same formula, but
  different structures.
• Examples Glucose and Fructose

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4. What are the big four?
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Three out of the 4 types of biochemical
macromolecules can be found on food nutrition
labels
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Look at the label to the left. 3 of the 4
macromolecules can be found in foods.
FAT
1____________________ 2____________________ 3___
_________________
(0 grams in this product)
Carbohydrates
(13 grams in this product)
Protein
(9 grams in this product)
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What is the fourth type of biochemical
macromolecule?
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4. What are the big four?

• Fats (we call them lipids)
• Carbohydrates
• Proteins
• Nucleic acids (DNA and RNA)

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When studying these biochemical molecules, we
are interested in finding out..

• what they do for living things.
• what they generally look like.
• what their monomers are.
• and how they may help the body gain energy to
  sustain life.
• SO, LETS GET STARTED!

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Great website for reference

• http//biomodel.uah.es/en/model3/index.htm

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5. Carbohydrates

• Molecules that form from atoms in C1H2O1 ratio
• Monomers Monosaccharides (simple sugars)
• Monosaccharides are usually sweet, white powdery
  substances (such as fructose, glucose) that form
  rings of carbon atoms.

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• Monosaccharides in general serve as direct, quick
  sources of energy for living organisms during
  cellular respiration, they are building blocks of
  many polymers
• Important monosaccharides
• Glucose
• Fructose

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• Disaccharides two monosaccharide molecules
  combine by dehydration synthesis to form
  disaccharides

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• Important disaccharides
• Lactose found in milk sugar
• Sucrose table sugar

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• Polysaccharides many (tens to hundreds) units
  of monosaccharides combine by dehydration
  synthesis
• Polysaccharides also separate to monosaccharides
  by hydrolysis while taking in water.

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• Important polysaccharides
• Starch made up of many glucose units, it is an
  important storage polysaccharide that is found in
  plant roots and other tissues. It stores
  monosaccharides that can be broken down later to
  release useful energy during cellular respiration
  ONLY IN PLANTS
• Glycogen also made up of many glucose units, it
  is an important storage polysaccharide in the
  liver and animal muscles. It can also be broken
  down to monomers to release energy during
  cellular respiration. ONLY IN ANIMALS
• Cellulose also made up of many glucose units.
  However, in this case the molecule is not easily
  broken down to its monomers. It is important for
  providing a rigid structure in plant cell walls.

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• Chitin made up of some nitrogen containing
  monosaccharides. It is an important
  polysaccharide that provide the solid structure
  of arthropods and fungi.

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6. Lipids

• a diverse group of molecules that are nonpolar
  and generally do not dissolve in water
• They mostly contain carbon, hydrogen, very few
  oxygen atoms, but some also have phosphorous.
• There are three distinct groups of lipids
• Simple lipids
• Phospholipids
• Sterols

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6A. Simple Lipids

• Very large molecules that form from 2 different
  kinds of monomers by dehydration synthesis
• 3 Fatty acids are long chains of carbon with
  oxygen at the end (can be saturated and
  unsaturated)
• 1 Glycerol smaller 3-carbon compound.

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• Simple lipids are important as storage materials
  in all living things. They can store twice as
  many calories as polysaccharides can. Oils
  (mostly from plants) contain more unsaturated
  fatty acids, while fats (animals) contain more
  saturated fatty acids.
• Simple lipids also dissolve vitamins
• http//biomodel.uah.es/en/model3/index.htm

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6B. Phospholipids

• Phospholipids phosphate containing lipids.
• Their monomers 1 glycerol 2 fatty acids
  (saturated or unsaturated) phosphate. These
  monomers combine by dehydration synthesis
• Phospholipids have both polar and nonpolar
  sections. As a result, they are able to dissolve
  in both type of solvents as well.
• They are important for living things because they
  form the borders of all cells (cell membranes)
  and also participate in forming many cell
  organelles.

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(No Transcript)
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6C. STEROLS

• Sterols are a highly nonpolar (hydrophobic) group
  of molecules.
• They occur naturally in plants, animals, and
  fungi, with the most familiar type of animal
  sterol being cholesterol.
• Cholesterol is vital to cellular function, and a
  precursor to fat-soluble vitamins and steroid
  hormones.
• 3-six sided rings and one 5-sided ring alcohol

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7. Proteins

• Protein- Polymer constructed from amino acid
  monomers.
• Only 20 amino acids, but make 1,000s of proteins
• Some are 100 a.a. in length some are thousands

3-D Protein
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7A. Protein Functions

• Each of our 1,000s of proteins has a unique 3-D
  shape that corresponds to a specific function
• Defensive proteins
• Antibodies in your immune system
• Signal proteins
• Hormones and other messengers
• Hemoglobin
• Delivers 02 to working muscles
• Transport proteins
• Move sugar molecules into cells for energy
  (insulin)
• Storage proteins
• Ovalbumin (found in egg white) used as a source
  of amino acid for developing embryos
• Most important roles is as enzymes
• Chemical catalysts that speed and regulate
  virtually all chemical reactions in cells
• Example, lactase

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7B. Amino Acid structure

• Proteins diversity is based on differing
  arrangements of 20 amino acids.
• Amino acids all have an amino group and a
  carboxyl group.
• R group is the variable part of the amino acid
  determine the specific properties of the 20 amino
  acids.
• Two main types
• Hydrophobic
• Example Leucine
• R group is nonpolar and hydrophobic
• Hydrophilic
• Polar and charged a.a.s help proteins dissolve
  in aqueous solutions inside cells.
• Example Serine
• R group is a hydroxl group

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7C. Amino Acid Dehydration

• Cells join amino acids together in a dehydration
  reaction
• Links the carboxyl group of one amino acid to the
  amino group of the next amino acid as a water
  molecule is removed.
• Form a covalent linkage called a peptide bond
  making a polypeptide.

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7D. Protein Structure

• Primary Structure
• Unique sequence of amino acids
• For any protein to perform its specific function,
  it must have the correct collection of amino
  acids arranged in a precise order.
• Example a single amino acid change in hemoglobin
  causes sickle-cell disease
• Determined by inherited genetic information.

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7D. Protein Structure

• Secondary Structure
• Parts of the polypeptide coil or fold into local
  patterns.
• Patterns are maintained by regularly spaced
  hydrogen bonds between the hydrogens of the amino
  group and the oxygen of the carboxyl groups.
• Coiling results in an alpha helix.
• Many fibrous proteins have the alpha structure
  over most of their length
• Example structural protein of hair
• Folding leads to a pleated sheet.
• Make up the core of many globular proteins
• Dominate some fibrous proteins, including the
  silk proteins of a spiders web

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7D. Protein Structure
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7D. Protein Structure

• Tertiary Structure
• Overall, three-dimensional shape of a
  polypeptide.
• Roughly describe as either globular or fibrous
• Generally results from interactions among the R
  groups of amino acids making up the polypeptide.

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7D. Protein Structure

• Quaternary Structure
• Results from association of subunits between two
  or more polypeptide chains.
• Does not form in every protein.
• Example, Hemoglobin

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8. Nucleic Acids

• DNA and RNA
• Deoxyribonucleic Acid (DNA)
• Monomers made up of nucleotides
• Nucleotides consist of
• A five carbon sugar, deoxyribose
• Phosphate group
• Nitrogenous base (Adenine, Guanine, Cytosine,
  Thymine)
• Double helix consists of
• Sugar-phosphate backbone held by covalent bonds
• Nitrogen bases are hydrogen bonded together A
  pairs with T and C pairs with G

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8A. Nucleotides of DNA
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8B. DNA

• Genetic material that organisms inherit from
  their parents.
• Genes
• Specific stretches of DNA that program amino acid
  sequences of proteins.

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8C. RNA

• Ribonucleic Acid (RNA)
• Intermediary for making proteins
• Single-stranded
• Also made up of monomers of nucleotides
• Nucleotide of RNA
• Sugar is ribose (not deoxyribose)
• Phosphate group
• Nitrogen bases (Adenine, Uracil (instead of
  Thymine, Guanine, and Cytosine)

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9. Enzymes

• (First half of chapter 5)
• Before we can understand how these important
  proteins function, we are going to look at
• Types of Energy
• Chemical Reactions
• ATP

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9A. Types of Energy

• Energy The capacity to perform work
• Potential energy
• A form of potential energy is chemical energy
  (energy of molecules)
• Kinetic energy
• A form of kinetic energy is heat

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9B. Chemical Reactions

• Chemical reactions can store or release chemical
  energy.
• endergonic a reaction where energy is taken in
  by the reactants to form the products (like
  dehydration synthesis or photosynthesis)
• exergonic a reaction where energy is released
  by the reactants to form the products (like
  cellular respiration)
• Frequently, exergonic reactions fuel endergonic
  reactions energy coupling

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9B. Chemical Reactions
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9C. ATP (adenosine triphosphate)

• ATP
• A modified nucleotide molecule that powers all
  cellular work directly.
• Its structure adenine, ribose and three
  phosphates are combined by dehydration synthesis

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9C. ATP

• Phosphorylation
• ATP molecules release phosphate groups to various
  other molecules. These molecules take in the
  phosphate by phosphorylation and get excess
  energy to perform various processes.
• When ATP releases a phosphate energy it
  produces ADP (adenosine diphosphate)
• ADP can turn back to ATP by taking in a phosphate
  and energy by phosphorylation

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9C. ATP
http//www.biologyinmotion.com/atp/index.html http
//student.ccbcmd.edu/biotutorials/energy/atpan.ht
ml
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9C. ATP

• The energy from ATP can be used for the following
  processes
• Chemical work (forming products from reactants)
• Mechanical work (contracting muscle)
• Transport work (moving substances into or out of
  the cell)

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10. Enzymes

• Enzymes are proteins that act as biological
  catalysts in living organisms.
• They speed up chemical reactions by lowering the
  activation energy of the reaction.

http//www.stolaf.edu/people/giannini/flashanimat/
enzymes/transition20state.swf
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10A. Enzyme Specificity

• Enzymes have a specific section called the active
  site that is able to bind with the reactants
  (substrates) of a chemical reaction
• Once the substrates bind to the active site, the
  active site changes shape and pulls the reactants
  together. As a result, the reaction occurs
  faster and more efficiently.
• The model that describes that enzymes change
  shape when bind with the substrate is called the
  induced fit model

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10B. Induced Fit Model
Animations http//highered.mcgraw-hill.com/sites
/0072495855/student_view0/chapter2/animation__how_
enzymes_work.html http//www.lpscience.fatcow.co
m/jwanamaker/animations/Enzyme20activity.html
http//www.northland.cc.mn.us/biology/biology111
1/animations/enzyme.swf
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10C. Enzyme Characteristics

• Three important special characteristics of
  enzymes
• They are specific
• They are efficient
• They are sensitive

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10D. Cofactors and Inhibitors

• Cofactors
• Many enzyme do not function without an additional
  group attached to them. This additional group is
  called a cofactor.
• Inhibitors
• Some substances can stop enzymes from functioning
  by attaching themselves to the active site of the
  enzyme. These are called inhibitors.
• Many inhibitors are used as poisons or drugs.