BIOL 101 1st Edition Lecture 4 Outline of Last Lecture I Importance of Water II Causes of Unusual Behaviors of Water III Unusual Properties of Water IV Aqueous Solutions and Their Properties V Acids Bases and pH VI Solute Concentration EXTRA CREDIT HW Problems VII Solute Concentration EXTRA CREDIT HW Solutions VIII pH EXTRA CREDIT HW Problems IX pH EXTRA CREDIT HW Solutions X QUIZ THURSDAY IN CLASS Outline of Current Lecture I Why Carbon II Isomers III Hydrocarbons IV Functional Groups V Chart of 6 Functional Groups VI Introduction to Macromolecules Chapter 5 Current Lecture Chapter 4 Carbon and Molecular Diversity These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute I Why Carbon a Atoms are small and form strong bonds valence of Carbon is 4 b Versatility in bonding bond to other Carbons or elements c Good Transport Form i CO2 easily crosses membranes d Carbon can form large complex and diverse molecules that have different functions e Organic molecules molecules that contain Carbon f Carbon Skeleton refers to the arrangement of carbon atoms in the molecule i Length how many atoms ii Shape straight chain branched chain ring iii Location and number of double bonds iv What other elements are covalently bonded to the skeleton II Isomers a These are compounds that have the same molecular formula but DIFFERENT structures b 3 kinds i Structural Isomers different in the covalent arrangement of atoms C 4H10 ii Geometric Isomers same covalent bonds but differ in spatial arrangement C 2O2H4 1 Because of the rigid double bond there is no rotation 2 Subtle difference affects biological activity iii Optical Isomers Sterioisomers Isomers that are mirror images of each other 1 Occurs when there are 4 different atoms or groups of atoms bonded to the same carbon atom 2 Asymmetric Carbon a carbon atom with 4 different atoms bonded to it 3 The 4 different groups can be arranged in space in 2 different ways that are mirror images of each other they cant superimpose 4 Speak of left or right handed as isomers hands are mirror images of each other D and L isomers 5 Usually only one of the forms is biologically active 6 Examples a Amino Acids only the L isomer is used to make proteins b Sugars only the D isomer is recognized III Hydrocarbons a Molecules containing only Carbon and Hydrogen b Major components in fossil fuels c Hydrocarbons are nonpolar hydrophobic lecture 2 so they don t dissolve in H 2O because water is polar lecture 3 d Nonpolar because the bonds between C and H are nonpolar covalent bonds electronegativity of C is 2 55 and H is 2 2 share electrons equally lecture 2 IV Functional Groups a Specific groups of atoms bonded to the carbon skeleton b Each functional group has specific chemical and physical properties c They behave consistently from one molecule to the next d Usually involved in chemical reactions e Can be thought of as molecular accessories change them and change the behavior V Functional Group Chart a Know i The names of the groups ii Their structures iii How they are attached to the carbon skeleton except phosphate iv Characteristics conferred by the group Name of the Group Structural Formula Characteristics Hydroxyl R O H Polarity solubility in H2O Carbonyl R C O H Polarity solubility in H2O Carboxyl or Carboxylic Acid R C Dissociates H acidity adds H decreases pH O O H Amine R N H Accepts H to become NH3 basic removes H increases pH H Sulfhydryl R S H Forms cross links stabilizes molecules Phosphate R O PO3H2 Used in energy transfer Chapter 5 Macromolecules VI Macromolecules a 4 Major Types i Proteins ii Carbohydrates iii Nucleic Acids iv Lipids b Large organic polymers large molecules made from many identical or similar subunits connected by covalent bonds These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute c Subunit monomer building blocks d Example of unity in life lecture 1 only 40 50 common monomers in all living things e Example of diversity in life lecture 1 hooking them in different ways creates many kinds of molecules utilizing the same small set of monomers f Polymers are formed from monomers by i Dehydration Synthesis the loss of H2O ii One monomer loses a hydroxyl group OH iii Other monomer loses a hydrogen atom H iv Those then bond to form H2O and the two monomers are bonded to each other v Dehydration Synthesis REQUIRES energy g Polymers are broken down into monomers by the opposite process i Hydrolysis adding H2O ii One monomer adds an OH group iii Other monomer adds an H atom iv The two monomers are now separate v Hydrolysis RELEASES energy These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute