AP Biology: Macromolecules Questions and Answers Graded A

AP Biology: Macromolecules Questions and Answers Graded A Macromolecules Molecules composed of thousands of atoms: the four main classes being carbohydrates, lipids, prteins, and nucleic acids Polymer Chainlike molecules, consisting of many similar or identical building blocks linked by covalent bonds. Monomer Make up polymers: connected by covalent bonds. Dehydration Synthesis (Condensation Reaction): Covalent bonds which connect monomers have distinct functions: One monomer provides a hydroxyle group and the other provides a hydrogen, creating water (as a biproduct) and a bond between the monomers. Hydrolysis Adding water to reverse dehydration synthesis, so the polymer recieves a hydrogen atom and a hydroxyl group Carbohydrates A macromolecule made up of C, H and O, with a 2:1 ratio between the hydrogen and oxygen. Monosaccharides Simple sugars with 1 ring: Provides immediate energy, classified by the amount of carbons Disaccharides Double sugars with 2 rings Polysaccharides Polymers, with many rings, joined by glucosidic linkages. Acts as an energy storage macromolecule, building materials for cells or whole organisms Maltose A disaccharide formed by joining the two glucose molecules: found in malt sugar Sucrose A disaccharide formed by joining glucose and fructose, major form of sugars in plants: found in table sugar Lactose A disaccharide formed by joining glucose and galactose. People who lack the enzyme to digest this sugar are "intolerant" Glucosidic Linkages the bond that bonds polysaccharides Starch During photosynthesis: glucose is a biproduct that is stored in plastids and chloroplasts Cellulose Made up cell walls of plants, using beta rings Glycogen An animal polysaccharide. Human produces excess sugar, highly branched. Humans and vertebrates store this in the liver and muscles Chitin Makes up the exoskeleton of pill bugs; extremely strong, contains nitrogen-containing appendage on each glucose. Structural support for the cell walls of many fungi. Lipids Literally no affinity for water (hydrophobic), nonpolar molecules. Have C, H and O, but not in a 2:1 ratio. Triacylglycerols (Fats): Store large amounts of energy, made up of 1 glycerol + 3 fatty acids -> 1 fat + 3 water molecules. Functions as energy storage, to cushion vital organs, and insulation. Glycerol An alcohol (contains a hydroxyl group) with 3 carbons and 3 OH's Fatty Acid Carboxyl group attached to a long carbon skeleton; many kinds, while there is 1 type of glycerol. Ester Linkage Joins 3 fatty acids to a glycerol, creating a triacylglycerol Saturated fatty acids Fatty acids with single bonds, hydrogen at every possible position, a straight shape, from an animal source. Solid at room temperature. Unsaturated fatty acids Fatty acids with double and single bonds, without hydrogens at every possible position, a kinked/bent shape, from a plant source. Liquid at room temperature. Phospholipid 2 fatty acids attached to a glycerol, with a phosphate group in the 3rd position. Have both hydrophobic and hydrophilic bonds Steroid A type of phospholipid: A carbon skeleton with 4 fused carbon rings, which are closely interlocked. ex., cholesterol Proteins Built up of 20 types of amino acids, which can unravel or denature in response to changes in pH, salt concentration, and temperature because they disrupt the bonds between parts of the protein Antibodies Bind to particular foreign substances that fit their binding sites Neurotransmitters Pass signals from one cell to another by binding to receptror sites on proteins in the membrane of the recieving cell Enzymes Recognize and bind to specific substrates, facilitating a chemical reaction Primary Structure The unique sequence of amino acids, determined by DNA. Changing this affects a protein's conformation and ability to function. Secondary Structure Results from hydrogen bonds at regular intervals doing the polypeptide backbone, typically developed as an alpha helix or a beta pleated sheet. Tertiary Structure The protein has folded up upon itself, held together by hydrogen bonds, ionic bonds, Van der Waals reactions, or disulfide bridges Quarternary structure Union of 2+ polypeptide subunits Enzymes Speeds up the rate of reactions, but are not consumed by the reaction. Lowers the activation energy of a reaction, and makes it easier to perform these reactions. Substrate A reactant that binds to an enzyme Active Site A pocket/groove on the surface of a protein on the surface of the protein into which the substrate fits. The substrate is held to this area through weak interactions, such as hydrogen bonds or Van der Waals. Lock and Key Hypothesis Substrates fit into enzymes like a key fits into a lock Induced Fit Hypothesis As the substrate binds, the enzyme changes shape leading to a tighter induced fit, bringing chemical groups into position to catalyze the reaction. Cofactors Non-protein factors, helping the enzyme fit substrates. ex: zinc, iron, copper Competitive Inhibitors Blocks the active site from having a substrate meet. Acts as a feedback mechanism Noncompetitive inhibitors Blocks the substrates at a place away from the active site. Allosteric Enzymes Enzymes that can change their shape: one shape is active (reaction occurs) and one is inactive (reaction doesn't occur) Nucleic Acids An organic compound made up of a pentose sugar, phosphate, and nitrogen base. The three types are DNA, RNA and ATP Ribonucleic acid (RNA) Many types of instructional nucleic acid, which is directed by DNA and contributes to protein production Deoxyribonucleic acid (DNA) Provides the genetic coding for organisms and directs RNA synthesis: synthesized through dehydration synthesis, connecting the sugar of one nucleotide to another with a strong phosphodiester. Nucleotide The building blocks of nucleic acids Pentose sugar Deoxyribose and ribose; a building block of nucleic acids Phosphate Makes DNA and RNA charged; a building block of nucleic acids Nitrogen base Adenosine, Thymine, Guanine, Cytosine, Uracil (RNA); building blocks of DNA. A+T are always together, and G+C are always together based on their properties. U is only found in RNA. Purines Adenosine, Guanine; have a double ring, where 1 6-membered ring joined to 1 5-membered ring Pyrimidines Thymine, Cytosine, Uracil; 1 6-membered ring Phosphodiester Link The bond between a sugar and a phosphate.