The Molecules of Life

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The Molecules of Life
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Matter, Energy, and Work

• Matter the collection of atoms and molecules of
  which everything is made.
• Anything that takes up space
• Energy is the ability to do work.
• Work a change in an objects position or form

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Potential and Kinetic Energy

• Potential energy is stored energy
• Kinetic energy is released energy

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Potential and Kinetic Energy

• Potential Energy
• Quarter Pounder, large fries, and a large shake
  1200 kcal
• granola bars 150 kcal
• energy bar 200 kcal
• 12 pizza 1200 kcal

• Kinetic Energy
• aerobics 422 kcal/hr
• house cleaning 250 kcal/hr
• Yoga 280 kcal/hr
• baseball 350 kcal/hr
• football 560 kcal/hr

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• Potential and Kinetic Energy

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Potential and Kinetic Energy
Diffusion or Osmosis
Digestion
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Energy

• Energy - The capacity to perform work.
• Thermodynamics - Study of energy and its
  conversions from one form to another.
• First Law - Energy is constant. It cannot be
  increased or diminished, only converted from one
  form to another.
• Second Law - Energy flow is uni-directional and
  there will always be less energy remaining after
  the conversion than existed before.

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The principle form of energy in the cell is ATP
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How do we get energy?The basic food groups
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Carbohydrates

• Carbohydrates are the most abundant organic
  compounds in nature.
• Monosaccharides - Simple sugars with backbones of
  three to seven carbon atoms. (Glucose and
  Fructose)
• Disaccharides - Formed when two monosaccharides
  bond together by dehydration synthesis. (Sucrose)
• Polysaccharides - Formed when several to many
  monosaccharides bond together. (Cellulose)

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Carbohydrates

• Simple Sugars
• Monosaccharides like glucose, and fructose
• Disaccharides like sucrose
• Complex Carbohydrates
• starch
• Cellulose

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Cellulose

• Glucose
• Structural carbohydrate in plant cells
• Most common carbohydrate on earth!
• Indigestible by nearly all organisms except...

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Starch

• Glucose
• Storage carbohydrate in plant cells
• Important source of energy for animals

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Monomers and Polymers

• Polymers - Formed when two or more small units
  (monomers) bond together.
• Condensation - Removal of water in the formation
  of a bond.
• Hydrolysis - Occurs when hydrogen becomes
  attached to one monomer and a hydroxyl group to
  the other.

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Hydrolysis (breaking apart) of starch or complex
carbohydrates yields simple sugars
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Lipids

• Lipids are fatty or oily substances that are
  mostly insoluble in water. (Fats and Oils)
• Typically store twice as much energy as
  carbohydrates.
• Most consist of chain with 16-18 carbon atoms.
• Saturated - No double bonds.
• Unsaturated - At least one double bond between
  carbon atoms.

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Lipids Triglyceride
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Saturated and UnsaturatedFatty Acids
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Trans-Fats and Hydrogenated Oils

• Trans-fats raise the level of LDL (low-density
  lipoprotein)
• LDL contributes to Coronary Heart Disease (CHD)

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Trans-Fats and Hydrogenated Oils
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Unnatural Fatty Acids

• Mono- and diglycerides in some ice creams
  processed foods give them a creamier texture
  without the cost of natural fats
• Olestra Olean 6-8 fatty acids attached to a
  sucrose molecule is a no calorie fat substitute

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Oils From Most Plants Are Good For You!

• Monounsaturated Oils
• Canola
• Olive oil
• Peanut oil
• Avocados

• Oils containing Saturated Fats
• Tropical oils like
• Coconut oil
• Palm oil

• Polyunsaturated Oils
• Corn
• Sunflower
• Safflower
• Sesame
• Many other nuts and seeds!

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Lipids

• Waxes - Lipids consisting of long-chain fatty
  acids bonded to long chain alcohol other than
  glycerol.
• Phospholipids - Constructed like fats, but one of
  the fatty acids is usually replaced by a
  phosphate group.

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Phospholipids are important in the cell membrane
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Protein Functions

• Enzymes- facilitate chemical reactions in the
  cell (the body)
• Structural organization- hair, nails,
  cytoskeleton
• Membrane transport (Diffusion and osmosis)
• Cellular regulation hormones
• Motility muscle movement and cytoskeleton
• Protective proteins body defenses such as
  antibodies

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Proteins, Polypeptides, and Amino Acids

• Proteins regulate chemical reactions in cells,
  and are usually very large and consist of one or
  more polypeptide chains.
• Polypeptides are chains of amino acids.
• Each amino acid has two functional groups plus an
  R group.
• Amino group (-NH2)
• Carboxyl group (-COOH)

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Proteins, Polypeptides, and Amino Acids

• Polypeptide Structure
• Primary Structure - A sequence of amino acids
  fastened together by peptide bonds.
• Secondary Structure - Coiling of polypeptide
  chains.
• Tertiary Structure - Maintained by coils between
  R groups.
• Quaternary Structure - Occurs when a protein has
  more than one kind of polypeptide.

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Storage Proteins

• Some plant food-storage organs store small
  amounts of proteins in addition to large amounts
  of carbohydrates.
• Seeds usually contain proportionately larger
  amounts of proteins in addition to their
  complement of carbohydrates.

• Essential amino acids are those that our body
  cannot make. Therefore we must get them from
  eating certain foods (meat, dairy, eggs)
• Non-essential amino acids are readily made by our
  bodies.

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Can you get enough protein from plants?

• There are about 20 different amino acids, eight
  of which must be present in the diet.
• These are the essential amino acids.
• Unlike animal proteins, plant proteins may not
  contain all the essential amino acids in the
  necessary proportions.
• However, a varied vegetarian diet means a mixture
  of proteins are consumed, the amino acids in one
  protein compensating for the deficiencies of
  another.

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Enzymes

• Enzymes are mostly large, complex proteins that
  function as organic catalysts under specific
  conditions.
• Work by lowering energy needed to activate a
  chemical reaction.
• Temporarily bonds with potentially reactive
  molecules at an active site.

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Raffinose
Galactose Sucrose
Alpha-galactosidase

Beano enzyme
soy products broccoli family
Enzymes are proteins
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• Enzymes
• All enzymes are proteins
• Catalyze chemical reactions
• Are not used up in a reaction (are recycled)

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Enzymes and Energy Transfer

• Enzymes are proteins that regulate most metabolic
  activities.
• Anabolism - Storing Energy.
• Photosynthesis reactions
• Catabolism - Consuming Stored Energy.
• Cellular Respiration

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Chloroplast
Mitochondria
Aerobic respiration Mitochondria (all eukaryotic
cells)
Photosynthesis Chloroplasts (some plant and algal
cells)
Light
CO2
CO2
Glucose

O2
O2
Glucose



ATP
ATP
H2O
H2O
photosynthesis
respiration
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Heterotrophs and Autotrophs