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ORGANIC MOLECULES & FUNCTIONAL GROUPS. VITALISM. Anything that was alive possessed a vital spark , while things that weren't alive...didn’t. So what is a vital spark ? Well, you can't see it, taste it, feel it, hear it, or smell it.
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VITALISM • Anything that was alive possessed a vital spark, while things that weren't • alive...didn’t. • So what is a vital spark? • Well, you can't see it, taste it, feel it, hear it, or smell it. • You can't capture it in a bottle or any other vessel; you can't transfer it from one object to another. You can't measure it or detect it. The only way to determine if an object had one was to determine if it was alive or not. MECHANISM • Biologists don't believe that there are any substances or materials which are exclusive to living things. • What makes something alive is not what it's made of; it's how it's put together and what activities (i.e, chemistry) go on within its structures.
Characteristics of life Response to the environment adaptation order reproduction Energy processing regulation Growth and development
Miller Urey Experiment Demonstrated that organic compounds can be created by fairly simple physical processes from inorganic substances. The experiment used conditions then thought to provide an approximate representation of those present on the primordial Earth.
WHAT’S THE DIFFERENCE BETWEEN ORGANIC COMPOUNDS & INORGANIC COMPOUNDS? ORGANIC INORGANIC
WHY IS CARBON SO SPECIAL? The versatility of carbon: Makes possible the great diversity of organic molecules
Where does the source of carbon for all organic molecules come from?
Carbon Chains Form the Skeletons of Most Organic Molecules What do you notice about these molecules?
Carbon (valence = 4) Nitrogen (valence = 3) Hydrogen (valence = 1) Oxygen (valence = 2) Name and Comments Space-Filling Model Molecular Formula Structural Formula Ball-and-Stick Model O H N C H (a) Methane CH4 C H H H H H (b) Ethane C2H6 C H C H H H Figure 4.4 H H (c) Ethene (ethylene) C C C2H4 H H Figure 4.3 A-C Hydrocarbons Have suffix –ane if single bonded. Found in fossil fuels Number of Bonds Carbon atoms can form diverse molecules by bonding to four other atoms
MOLECULAR SHAPE & FUNCTION • Shapes are determined by the positions of the atoms’ orbital. • Molecular shape is very important in living cells. • It determines how the molecules recognize & respond to each other. • If they are complimentary; they will bond
ISOMERS COMPOUNDS THAT HAVE THE SAME NUMBERS OF ATOMS OF THE SAME ELEMENTS BUT DIFFERENT STRUCTURES. (THESE MOLECULES THEREFORE HAVE DIFFERENT PROPERTIES)
Both of the molecules below are C5H12 Why are there different forms of the same chemical formula? Because carbon can bond to either hydrogen or another carbon What would it take to make these molecules identical? Breaking and reforming a covalent bond What type of isomer are molecules that have more than 1 structural form? Structural Isomer
LIGHTER FLUID REFRIGERANT
Both of the molecules below are C2H4Cl2 cis trans Why are there different forms of the same chemical formula? Because the H and Cl can bond in any order around the central carbon atoms What would it take to make these molecules identical? Rotation around the carbon-carbon double bond What type of isomer are molecules that have double bonds & more than 1 geometric arrangement? Cis-trans isomers/ geometric isomers
EX: A VISUAL PIGMENT IN OUR EYES CALLED RHODOPSIN • It changes shape when it absorbs light from the cis isomer to the trans isomer. • Process known as “bleaching” • When you move from a very bright environment to a very dark. • There is too little light to stimulate your cones, & it takes a few min. for your bleached rods to become fully responsive again.
Both of the molecules below are CHIBrCl dextro levo D isomer L isomer In what way are these molecules different from each other? They are mirror images of each other What would it take to make these molecules identical? Breaking and reforming a covalent bond What do we call these types of isomers? Enantiomers
Functional groups Are the chemically reactive groups of atoms within an organic molecule THE COMPONENTS OF ORGANIC MOLECULES THAT ARE MOST COMMONLY INVOLVED IN CHEMICAL REACTIONS
NOTICE THE MOLECULES ON THE RIGHT. THEY DIFFER ONLY IN THE FUNCTIONAL GROUP. Produce differences in males vs females.
Creating your functional group poster Functional Groups being presented: -hydroxyl -carbonyl -amino -carboxyl -sulfhydryl -phosphate -methyl
Create a large visual aid that conveys the following information: • Draw your functional group • Describe the physical properties your functional group adds to a molecule. • Give the chemical naming suffix • List examples • Record any additional information associated with your functional group. YOU HAVE 15MINUTES TO COMPLETE YOUR POSTER FOR PRESENTING
A Few Discussion Questions Yes, most do. EX: amino acids have both the amino group and the carboxyl group. • Can a molecule have more than one functional group? • Which group(s) would change the pH of a solution? In what way? • Which of the functional groups would hydrogen bond? • Which groups are hydrophillic? • Carboxylic acids & amines (bases) All of them All of them…except methyl
Carbohydrates (2 groups) • Monomer • Polymer • Chemical structural differences • Examples of each & why they are important • One group will present simple carbohydrates • One group will present complex carbohydrates • Glycosidic linkage
Lipids • 3 major types • What is different about each of them • Chemical structure differences • Saturated vs unsaturated • Examples of why/how they are important
Nucleic acids • Monomer • Polymer • 2 types • Chemical structure • Differences between them • Similarities between them • Examples of why/how they are important
Proteins • Monomer • Polymer • Basic chemical structure of a monomer • What is different about the different about each type of monomer? • Examples and why/how they are important
SYNTHESIS AND BREAKDOWN OF POLYMERS • Enzymes help • Dehydration (Condensation) reaction • To connect monomers together • A water molecule is released • One molecule gives up a hydroxyl group & the other a hydrogen • Hydrolysis • Polymers are broken apart to monomers • A water molecule is added to split apart the monomers EX: Digestion
VARIOUS MONOSACCHARIDES What do all of these sugars have in common? They are made of one carbonyl group and several hydroxyl groups. What’s the difference between the top row of sugars compared to the bottom row? The top sugars have their carbonyl group at the end of the carbon skeleton & the bottom ones have their carbonyl group in the middle Identify the difference between glucose & galactose.
What are the monomers used to form? Disaccharides and polysaccharides
Where does the polysaccharide bond occur and how? At an oxygen off the 1’ carbon using a dehydration reaction called glycosidic linkage. WHAT IS GLYCOSIDIC LINKAGE? Covalent bond between 2 monosaccharides through a dehydration reaction. • A water molecule is released • One molecule gives up a hydroxyl group & the other a hydrogen
2 Different Structures of Glucose Linear Ring Write down how the linear structure becomes a ringed structure. Be as specific as possible. The ketone or aldehyde react with the hydroxyl group in aqueous solution Why does this happen?
Carbohydrates • Also referred to as sugars • Provide building materials and energy storage • Are molecules that contain carbon, hydrogen and oxygen in a 1:2:1 ratio • Are of two main types • Simple carbohydrates • Complex carbohydrates
WHICH OF THESE IS A MONOMER OF CARBOHYDRATE? WHAT DO WE CALL THIS MONOMER? HOW CAN YOU TELL? Glucose Carbohydrate monomers generally have molecular formulas that have some multiple of the unit CnHxOn in ratios of CH2O WHAT IS THE CHEMICAL SUFFIX USED FOR CARBOHYDRATES? -ose
Glucose Sucrose Simple Carbohydrates • Monosaccharide • Consist of one subunit • EX: glucose, fructose, galactose • Disaccharide • Consist of two subunits • EX: sucrose, maltose, lactose Helps secrete lactose Chemical fuel for the body Formed by a dehydration reaction Makes fruit sweet Type of carbohydrate transported from leaves to roots Chemical formula: C6H12O6 Glycosidic linkage
Complex Carbohydrates • Consist of long polymers of sugar subunits • Few hundred to a few thousand • Also termed polysaccharides • Serve as energy storage and/or building material for structure and/or protection
Animals store energy in the form of glycogen, glucose polymer, in their liver and muscles. Plants store energy in the form of starch which are made from many glucose molecules Starch granules
Plants Use Cellulose in their Cell Walls to give them structure & protection Primary component of plant cell walls. Most animals cannot digest this. Cows can.
We (humans) can eat & digest starch but we cannot digest cellulose. WHY???
The hydroxyl group attached to the number 1 carbon is positioned either below or above the plane of the ring. GLYCOSYLIC LINKAGE GIVE THESE CARBOHYDRATES DIFFERENT SHAPES: • Starch = helical • Cellulose= straight non branched It’s all about the linkage alpha vs beta
Your body contains enzymes (amylase) that break starch down into glucose to fuel your body. But we humans don't have enzymes that can break down cellulose. • Some animals do:
Cellulose is a lot stronger than starch. cellulose is strong enough to make fibers from, and make rope, clothing, etc. • Cellulose doesn't dissolve in water the way starch will, and doesn't break down as easily. • This is a good thing… since our clothes are made of cellulose, wooden park benches and wooden houses would all dissolve after one good rain.
CHITIN Builds exoskeletons used by arthropods. Fungi use this instead of cellulose for their cell walls. GLUSOSE (beta) WITH A NITROGEN APPENDAGE
Lipids • Large nonpolar molecules that are insoluble in water • They are NOT polymers but they are large molecules assembled from smaller molecules. • Three major types • Triglycerides • Phospholipids • Steroids
Triglycerides • Used for long-term energy storage • Composed of three fatty acid chains (hydrocarbon tails) linked to glycerol • EX: Fats & oils
Types of fatty acids • Fatty acids can be saturated or unsaturated Most plant fats Most animal fats
Saturated fats & Trans Fats: Linked to coronary disease Trans fats are worse than saturated fats. Trans fats are produced artificially where saturated fats are natural Denmark has banned trans fats in restaurants.