Biochem Chapter 2

Front 1

hydrolysis

Back 1

cleavage of a bond, such as an anhydride or peptide bond, by the addition of the elements of water, yielding two or more products

Front 2

condensation

Back 2

formation of a bond accompanied by the release of the elements of water from the joining atoms

Front 3

Henderson-Hasselbalch equation

Back 3

an equation relating the pH, the pK{a}, and the ratio of the concentrations of the proton acceptor (A-) and proton donor (HA) species in a solution

Front 4

buffer

Back 4

a system capable of resisting changes in pH, consisting of a conjugate acid-base pair in which the ratio of proton acceptor to proton donor is near unity

Front 5

titration cure

Back 5

a plot of the pH versus the quivalents of base added during tiration of an acid

Front 6

pK(a)

Back 6

the negative logarithm of an equilibrium constant

Front 7

dissociation constant K{a}

Back 7

Equilibrium constants for ionization reactions are usually called ionization or dissociation constants, often
designated K{a}

Front 8

conjugate acid-base pair

Back 8

a proton donor and its corresponding deprotonated species; for example, acetic acid (donor) and acetate (acceptor)

Front 9

pH

Back 9

the negative logarithm of the hydrogen ion concentration of an aqueous solution

Front 10

ion product of water K(w)

Back 10

the product [H+][OH-] in aqueous solutions at
25 C always equals [1x10^14] M

Front 11

equilibrium constant K(eq)

Back 11

a constant, characteristic for each chemical reaction; relates the specific concentrations of all reactants and products at equilibrium at a given temp and pressure

Front 12

hypotonic

Back 12

describes a solution of lower osmolarity than that from which it is separated by a semipermeable membrane

Front 13

hypertonic

Back 13

describes a solution of higher osmolarity than that from which it is separated by a semipermeable membrane

Front 14

isotonic

Back 14

describes a solution of the same osmolarity as that from which it is spearated by a semipermeable membrane

Front 15

osmosis

Back 15

bulk flow of water through a semipermeable membrane into another aqueous compartment containing solute at a higher concentration

Front 16

hydrophobic interactions

Back 16

the association of nonpolar groups, or compounds, with each other in aqueous systems, driven by the tendency of the surrounding water molecules to seek their most stable (disordered) state

Front 17

micelle

Back 17

an aggregate of amphipathic molecules in water, with the nonpolar portions in the interior and the polar portions at the exterior suface, exposed to water

Front 18

amphipathic

Back 18

containing both polar and nonpolar domains

Front 19

hydrophobic

Back 19

nonpolar; describing molecules or groups that are insoluble in water

Front 20

hydrophillic

Back 20

polar or charged; describing molecules or groups that associate with (dissolve easily in) water

Front 21

bond energy

Back 21

the energy required to break a bond

Front 22

hydrogen bond

Back 22

a weak electrostatic attraction between on electronegative atom (i.e. nitrogen or oxygen) and a hydrogen atom covalently linked to a second electronegative atom