Chem GOB Exam 4

• acid


  proton donators; carboxylic acids are acids (COOH)
• base


  proton acceptors; amines are bases (-NH2)
• oxidation


  the loss of electrons
• reduction


  the gain of electrons
• cis and trans


  cis (same side); trans (opposite side)

  
• London dispersion forces


  weakest intermolecular force caused by temporary dipoles
• Dipole-dipole attractions


  occur between polar molecules
• hydrogen bonds


  strongest intermolecular force, occurs between a hydrogen atom bonded to an electronegative atom
• heterocyclic amines

  organic compounds containing both a heterocyclic ring structure and an amine functional group
• carbohydrates


  have the general formula (CH2O)n, where n is the number of carbon atoms; they typically contain hydroxyl groups and an aldehyde and ketone functional group
• monosaccharides


  single sugar molecules
• disaccharides


  formed from two monosaccharide units
• polysaccharides


  polymers of many monosaccharide units
• aldose


  contains an aldehyde functional group
• ketose


  contains a ketone functional group
• Triose, tetrose, pentose, hexose, heptose


  carbons with 3, 4, 5, 6, and 7 carbons respectively
• Aldohexose is a hexose sugar with an aldehyde functional group
• Stereoisomers


  molecules with the same molecular formula but different arrangements of atoms
• chiral carbons


  carbons with four different substituents
• enantiomers


  stereoisomers that are non-superimposable mirror images of each other
• diastereomers


  stereoisomers that are not mirror images of each other
• D- and L- designations

  D- sugars have the OH group on the right; L- sugars have an OH group the left
• Cyclic monosaccharides


  monosaccharides that form cyclic structures between the carbonyl group and a hydroxyl group
• Lipids


  insoluble in water, and function in energy storage, membrane structure, vitamins, and hormones
• Fatty acids


  long hydrocarbon chains with a carboxylic acid group at one end
• Saturated fatty acids


  have single bonds between carbon atoms; have high melting points and are solid a room temp
• Unsaturated fatty acids


  have one or more double bonds between carbon atoms and can either be cis or trans; low melting point and liquid at room temp
• Triglycerides


  Esters composed of three fatty acids with a glycerol molecule
• mixed triglycerides


  triglycerides with two or three types of fatty acids attached to the glycerol backbone
• hydrophobic and hydrophilic


  lipids have hydrophobic tails (nonpolar) and hydrophilic heads (polar)
• phospholipids


  form the main structural component of the cell membrane; also contain phosphorus
• sphingolipids


  contain sphingosine backbone instead of a glycerol one
• glycosphingolipids


  sugar-containing lipids
• cholesterol


  maintain membrane fluidity and stability
• Steroids


  these are a four-ring structure consisting of three cyclohexane rings and one cyclopentane ring
• Cholesterol


  most abundnt steroid in the human body; abundant can be identified by its similar steroid structure; serves as a precursor for steroid hormones and bile acids
• passive diffusion


  movement of molecules across membranes from high to low concentration gradient without the use of energy
• facilitated diffusion

  movement of molecules across membranes from high to low concentration through a protein channel; driven by equilibrium
• active transport


  movement of molecules across membranes from low to high concentration through a protein channel driven by energy (ATP)
• protein function


  enzymatic activity, structural support, transport of molecules, defense against foreign substances, regulation of cellular processes