Organic Molecules The molecules of life. The building blocks of life.

Organisms are composed of: 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? Condensation Reaction ( aka dehydration synthesis) - Water is released when a bond forms. and H 2 O

Condensation Reaction

How are POLYMERS broken down into MONOMERS? Hydrolysis Reaction - Water is added to break bonds H2OH2O

Hydrolysis

Making Biological Molecules Condensation Reaction (Builds Macromolecules) Hydrolysis Reaction (Breaks down Macromolecules) and H 2 O H2OH2O

4 Types of ORGANIC Macromolecules of Life 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: C 6 H 12 O 6 –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.

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

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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? – Proteins – Lipids – Carbohydrates -4 calories / gram -9 calories / gram -4 calories / gram How do we measure ENERGY in food? CALORIES!