Do Now Make a list of foods that you eat and categorize them How will you categorize? Why? What is in each one?
Prefixes and Suffixes to know carbo- =“coal” di- = “two” hydro- =“water” mono- =“one” poly- =“much” -ase = “enzyme” -hydrate = “water” -ose =“sugar” -philic = “loving” -phobic =“fearing” -saccharide = “sugar”
Organic Molecules organic molecules: carbon based molecules Carbon can form bonds with one or more other carbon atoms, producing an endless variety of carbon skeletons hydrocarbons: composed of only carbon and hydrogen Important as fuels Methane (CH 4 ) - natural gas Energy-storing fat molecules
Inorganic Molecules inorganic molecules: non- carbon based Ex. Water, O 2, NH 3
Functional Groups functional groups: group of atoms within a molecules that interact in predictable ways with other molecules Hydroxyl group Called alcohols Polar Soluble in water Carbonyl group Ketones and aldehydes Polar Some sugars Carboxyl group Carboxylic acids Polar and soluble Acidic In amino acids Amino groups Amino acids Slightly polar basic
Monomers and Polymers monomers: small molecular units form a larger similar combination of hundreds or millions of atoms polymers: long chains of repeating monomers Branching chains or folding Every living cell has thousands of different kinds Made from a collection of fewer than 50 kinds of monomers 4 main categories Carbohydrates -- Proteins Lipids -- Nucleic acids
Building and Breaking Polymers dehydration reaction: each time a monomer is added to a chain, a water molecule is released hydrolysis reaction: water is added to a polymer to break it down Molecules in food are polymers and need to be broken apart to be available to your cells Monomers break down to obtain energy to make new polymers
5.2 Carbohydrates carbohydrate: organic compound made up of sugar molecules Sugars contain carbon, hydrogen and oxygen Ratio 1C:2H:1O Glucose= C 6 H 12 O 6
Monosaccharides monosaccharide: simple sugar that contains just one sugar unit Glucose, fructose glucose: exists in straight-chain and ring-shaped forms Main fuel supply for cellular work Unused molecules are incorporated into larger carbs or to make fat
Disaccharides disaccharide: “double sugar”; two monosaccharides combined by dehydration reaction sucrose: most common; made of glucose and fructose Major carb in plant sap and nourishes plants Table sugar processed from sugar cane stems
Polysaccharides polysaccharide: long polymer chains made up of simple sugar molecules Complex carbohydrates glycogen: polysacch found in animals that act as a storage for excess sugar Chain of many glucose monomers, but arte more highly branched than a starch monomer In humans, most glycogen is stored as granules in liver and muscle cells and break down when the body needs energy
Plant Polysaccharides starch: found in plant cells and consists entirely of glucose monomers Chains branch and coil up in loops “sugar stockpile” =stored energy cellulose: serves at building materials; protect cells and stiffens plant Many glucose monomers Multiple chains are linked by hydrogen bonds to form cable-like fibers in the tough plant cell walls Does not dissolve in water
How to test for the presence of carbohydrates in food Glucose: glucose strip (easy) Benedict’s test: add Benedict’s solution, place tube in boiling water for 5 minutes. Look for color change to red/brown Starch Drop iodine on the product or solution Changes to a purpleish black if starch is present
Do Now Complete the Carbohydrates section of the chart
5.3 Lipids lipids: class of compounds that is hydrophobic (water- fearing) Act as a boundary that surrounds and contains the aqueous contents of your cells Others circulate as chemical signals Some are fats which store energy
Fats fats(triglyceride): a 3-carbon backbone(glycerol) attached to 3 fatty acids(long hydrocarbon chains) Solid or liquid Fatty tissues cushion organs and provide body with insulation saturated fats: all fatty acid chains contain the maximum possible number of hydrogen atoms All single bonds Solid at room temp Animal fats unsaturated: less than max. number of H atoms in one or more fatty acid chains Some double bonded Liquid at room temp. Most plant and fish oils
Steroids steroids: carbon skeleton forms 4 fused rings Different functional groups attached to rings Different than fats in structure and function, but still hydrophobic Cholesterol Sex hormones Cortisol Vitamin D
Cholesterol cholesterol: essential molecule found in cell membranes Starting point from which your body produces other steroids makes the lipid bilayer less deformable and decreases its permeability
Links to cardiovascular disease LDL = low density lipoprotein “bad” HDL = high density “good” Triglycerides(fat)
Lipid Tests Paper Bag Test Place the food on a paper bag Positive: leave a “stain” on the bag Emulsion (Ethanol) Test Add the food sample to 2 cm 3 of ethanol, shake well. Allow to settle in a test tube rack for 2 minutes for food to dissolve in ethanol. Empty any clear liquid into a test tube containing 2 cm 3 of distilled H 2 O. A MILKY-WHITE EMULSION is a positive result: lipid is present. If the mixture remains clear, there are no fats present in the sample
Do Now 1. List 3 functions of proteins. 2. What foods are proteins found in? 3. What is the purpose of an enzyme?
5.4 Proteins protein: a polymer constructed from a set of just 20 kinds of monomers called amino acids. responsible for almost all of an organism’s functioning Enzymatic, transport, structure, storage hormonal, receptor, contractile, defensive
Protein Structure amino acid: monomer that consists of a central carbon atom bonded to four partners (carbon forms 4 bonds) three of the central carbon’s partners are the same in all amino acids the “side group” or the “R-group” is responsible for the particular chemical properties of each AA. Polypeptide: chain of amino acids that make up a protein dehydration reaction between amino group of one and a carboxyl of the next proteins = one or more polypeptide chains most chains are at least 100 AA
Shape polypeptides are precisely twisted, folded, and coiled into a unique shape for each protein influenced by the surrounding environment which is usually aqueous hydrophilic and phobic to different sides
Denaturation Denaturation: unfavorable change in pH, temperature, or other quality of the environment that causes the protein to unravel and lose shape (ex. frying an egg; albumin is egg white which turns from clear to white)
Protein Test Biurets To a test tube, add 40 drops of liquid to be tested. If testing more than one liquid, label each test tube with a marker. Add 3 drops of Biuret reagent solution to each test tube. Shake gently to mix. Note any color change. Proteins will turn solution pink or purple.
Do Now What are enzymes made of? What is the purpose of them?
5.5 Enzymes enzymes: specialized proteins in organisms that exist as catalysts they provide a way for chemical reactions to occur at normal temperature does not supply activation energy, but it lowers the energy requirement barrier each enzyme is specific to one reaction Always recycled pH and temp can affect function
Catalysts Catalysts: compounds that speed up chemical reactions activation energy: activates the reactants and triggers a chemical reaction “start-up” energy heat can provide activation energy, but may cause other reactions
How Enzymes Work the shape of the enzyme fits the shape of only particular reactant molecules substrate - a specific reactant acted upon by an enzyme active site - the substrate fits into a particular region of the enzyme can change shape slightly to fit snugly will accept two substrates into adjacent sites
Nucleic Acids DNA: dexoyribose nucleic acid RNA: ribose nucleic acid