Download Organic Molecules

Organic Molecules
The molecules of life.
The building blocks of life.
Organisms are composed of:
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Water
Carbohydrates
Lipids
Proteins
Nucleic acids
MACROMOLECULES
Organic Molecules
• The Building blocks of life (US!)
• ORGANIC (Scientific Meaning):
Compounds that contain CARBON;
usually in ring or chain formation
–Carbon is usually bonded with
Hydrogen & Oxygen (C, H, O)
Carbon Atoms: Building Blocks of Macromolecules
• Total of 6 Electrons, 4 Valence
Electrons
• Carbon can form:
– four covalent bonds
– Single, Double, Triple or
Quadruple bonds
– Each bond shares a PAIR of
electrons
• Allows Carbon to make LARGE
molecules (macromolecules)
Carbon Bonds to Build a Variety of
Shapes
• Straight chains
• Branched chains
• Rings
Macromolecules aka Polymers
• Macromolecules
– aka POLYMERS (“many parts”) which are
made of smaller units, linked together,
called MONOMERS (“one part”)
How do MONOMERS form POLYMERS?
and H2O
Condensation Reaction (aka dehydration synthesis)
- Water is released when a bond forms.
Condensation Reaction
How are POLYMERS broken down into
MONOMERS?
H2O
Hydrolysis Reaction
- Water is added to break bonds
Hydrolysis
Making Biological Molecules
and H2O
Condensation Reaction (Builds Macromolecules)
H2O
Hydrolysis Reaction (Breaks down Macromolecules)
http://www.cengage.com/biology/discipline_content/animations/reaction_types.html
4 Types of ORGANIC Macromolecules of Life
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Carbohydrates
Lipids
Proteins
Nucleic Acids
1. Which 3 Macromolecules can be found in foods
& beverages?
2. Can you think of foods that are high in each of
the 3 macromolecules?
3. Why do we need Carbs, Lipids & Proteins in our
diet?
Carbohydrates
–Carbo = carbon, hydrate = water
–Organic compound that contains
Carbon, Hydrogen, Oxygen in a 1:2:1
ratio
• Glucose: C6H12O6
–Function: quick energy supply, cell
identity (found on cell membranes)
–“carb loading” is used by cells to store
energy
–End in “–ose” indicates carb
– Examples:
• Monosaccharides (glucose, fructose,
galactose)
• Disaccharides (sucrose, lactose, maltose)
• Polysaccharides (cellulose & starch
(plants), glycogen)
ENERGY is stored in the BONDS
Which chemical reaction breaks downs the
polysaccharide into monosaccharides?
Carbs
• Starch = long-term energy storage for
plants, made of chains of GLUCOSE
Carbs
• Cellulose = glucose polymer that forms the
cell walls of plants gives plants structural
support.
Carbs
• Glycogen = long-term energy storage for
animals, stored in the liver.
http://www.teachertube.com/viewVideo.php?video_id=43700
http://www.youtube.com/watch?v=7b2NNoWdmsY
Simple vs Complex Carbs
• Simple Sugars: table sugar, molasses, honey,
alcohol, white bread, white pasta, white rice,
fried chips, sugary cereals, fruit juices, candy, and
milk
– Nutritionally “empty”
– Excess turned to fat
• Complex Sugars: vegetables, whole grain breads
and pastas, beans, peas, brown rice, sweet
potatoes, oats, fruits, and whole grain cereals
– Contains Fiber
– Controlled digestion, used slower & less likely to turn
to fat
Lipids
• Function: Stored energy & controlling water
movement
• Composed of: fatty acid and glycerol (carb made
from glucose in the body), Carbon, Hydrogen &
Oxygen
• Hydrophobic & Non-polar: do not dissolve in polar
molecules such as water, oil & water do NOT mix
• 3 Groups:
– 1. true fats: glycerols, triglycerides (in food)
– 2. Phospholipids: make up cell membranes
– 3. Steroids (cholesterol) & Waxes
Fats: Triglycerides
• Fats: composed of 1 glycerol and 3 fatty
acids (triglyceride)
• 2 Types of Fats:
–Saturated: Do NOT contain any double
bonds between the carbons
–Unsaturated: Do contain one or more
double bonds between the carbons
1 Glycerol + 3 Fatty Acid Tails
Phospholipids
• Made of 1 phosphate
molecule and 2 fatty
acid tails.
• Make up our Cell
Membranes
• The phosphate head is
hydrophilic
• The fatty acid tails are
hydrophobic.
Steroids
• Lipids characterized by a 4-carbon
skeleton.
• Cholesterol is an important steroid found
in all animal tissue.
– Strengthens cell membranes
– Too much builds up in blood and clogs
arteries
http://www.teachertube.com/viewVideo.php?
video_id=43703
Proteins
– Function: structure & support of cells, chemical
reactions
– Made up of Carbon, Hydrogen, Oxygen &
Nitrogen
– Monomers are AMINO ACIDS
• Held together by peptide bonds
Chemical Reactions
• All chemical reactions (metabolism) need ENERGY.
• Activation energy: the energy required for a
chemical reaction to begin
Energy is required for all biochemical
reactions…
• ENZYMES are proteins that acts as a catalyst to
speed up the rate of a reaction
– They decrease the activation energy needed
to begin the reaction
– Names end is “ase” (Lactase, DNA
Polymerase)
• Do not work alone: Enzyme & Substrate pair
Chemical Reactions
• Enzyme-Substrate Pair
– Enzyme: the catalyst that speeds up reactions
– Substrate: substance that needs to be changed
(broken down)
– Active site: location where substrate binds to
enzyme
– Enzymes are unique:
• Never change shape or form!
• Only fit one substrate!
• Can be reused!
Enzymes
Lower a
Reaction’s
Activation
Energy
• Enzymes have to physically fit with a
substrate.
• VERY SPECIFIC, there is a specific binding
site
• “Lock & Key” Model
Enzymes need Optimum Conditions to Work!
• Temperature: an increase will cause proteins to
break down
• pH
• Enzyme-Substrate Concentration: equal amount
of enzyme and substrate particles
• If we did not have enzymes, chemical
reactions would occur too slow to sustain
life.
Diabetes: Enzymes
• Insulin: protein (51 amino acids long) that
breaks down polysaccharides into Glucose
– Glucose is small enough to be absorbed by cells
for energy
– When there is an excess of Glucose, it is stored in
the liver as Glycogen
• Glucagon: protein that is released by cells to
convert Glycogen into Glucose during periods
of time where no food is eaten
RECAP…
• Why is Carbon important to life?
• 4 Classes of Macromolecules?
• Carbohydrates
– Function?
– Structure?
– 3 Types? Examples?
– Polysaccharides in Plants? Animals?
RECAP…
• Proteins
– Functions?
– Elements composed of?
– 3 Levels of structure?
– Purpose of Enzymes?
– 3 conditions necessary for Enzyme function?
Warm Up
1. What are the 2 components of ALL lipids?
2. What 2 purposes do all lipids have for our
bodies?
3. Why are true fats also called “triglycerides”?
4. What is the difference between a saturated
and unsaturated fat?
Nucleic Acids
• Function: store and transfer genetic information
within a cell
• Types:
• DNA: Deoxyribonucleic Acid
– Holds our Genetic code in chromosomes, “code” is
translated to make PROTEINS
• RNA: Ribonucleic Acid
– Assists DNA in making proteins
(Nucleic Acids Cont…)
• Made up of Nucleotides
(monomer)
– 5 carbon sugar: Deoxyribose
or Ribose
– Phosphate
– Nitrogen Base
THINK!
• Which contains more energy?
- 4 calories / gram
–Proteins
- 9 calories / gram
–Lipids
–Carbohydrates - 4 calories / gram
• How do we measure ENERGY in food?
• CALORIES!