L1 The Foundation of Biochemistry

A  FALSE

B  TRUE

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  FALSE

B  TRUE

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  FALSE

B  TRUE

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  It increases the activation energy

B  It increases the yield

C  It increases the rate

D  It increases the heat of reaction

A  Not all chemical reactions respond to catalysts

B  A catalyst will increase the activation energy in both directions; therefore, no shift in the position of equilibrium will result.

C  Equilibrium constants are not affected by adding a catalyst since no shift in the position of equilibrium occurs.

D  The position of equilibrium is not affected by adding a catalyst since a catalyst speeds up both the forward and back reactions by exactly the same amount.

A  decreasing the activation energy

B  increasing the energy of the transition state

C  increasing the activation energy

D  decreasing the amount of free energy released

E  increasing the amount of free energy released

A  heterotrophic

B  anabolic

C  autotrophic

D  amphibolic

E  catabolic

A  A reaction with a negative Gibbs free energy change of reaction is called an exergonic reaction

B  If the Gibbs free energy change for a reaction is negative, the reaction happens spontaneously

C  The Gibbs free energy change is the proportion of the enthalpy change of a reaction that is used to increase the entropy

D  The Gibbs free energy is represented by the symbol G

A  Exothermic

B  Endothermic

A  FALSE

B  TRUE

A  positive

B  negative

C  zero

D  infinite

A  nonspontaneous

B  backward

C  forward

D  spontaneous

A  reverse

B  both forward and reverse

C  Reaction stops

D  forward

A  A neutralization reaction with equal number of moles of an acid and a base.

B  A steady state in which matter is entering and leaving the system at a constant rate.

C  A state of balance in a chemical reaction where the speed of the forward reaction is unequal to the reverse reaction.

D  A chemical reaction in which the forward and reverse reactions are occurring at the same time and at the same rate.

A  the forward process is spontaneous but the reverse process is not

B  the free energy change is 0

C  both forward and reverse processes have stopped

D  the reverse process is spontaneous but the forward process is not.

A  is considered reversible

B  is considered irreversible

A  less activation energy is needed than for an endergonic reaction

B  products have less energy than reactants

C  products have more energy than reactants

D  more activation energy is needed than for an endergonic reaction

A  The reactions are rapid

B  A net input of energy from the surroundings is required for the reactions to proceed

C  The reaction goes only in a forward direction: all reactants will be converted to products, but no products will be converted to reactants

D  The products have more total energy than the reactants

E  The reaction proceeds with a net release of free energy

A  coupling them to the hydrolysis of ATP

B  manipulating the concentrations of products and reactants such that ΔG < 0

C  coupling them with exergonic reactions via a common intermediate

D  all of the above

A  at equilibrium

B  endothermic

C  exothermic

D  exergonic

E  endergonic

A  Adding a reactant always shifts a reversible reaction in the direction of reactants.

B  Adding a product causes a reversible reaction to shift in the direction of the formation of the reactants.

C  Removing a reactant always shifts a reversible reaction in the direction of reactants.

D  Removing a product shifts a reversible reaction in the direction of formation of products.

A  Keq = 0.0

B  Keq = 3.5

C  Keq =6.0×10^-4

D  Keq = 0.002

A  endothermic

B  exergonic

C  at equilibrium

D  exothermic

E  endergonic

A  the reverse reaction has stopped.

B  the sum of the concentrations of A and B must equal the sum of the concentrations of C and D.

C  the forward reaction has stopped.

D  both the forward and the reverse reactions have stopped.

E  neither the forward nor the reverse reaction has stopped

A  At equilibrium, ΔG = 0

B  If ΔG for a reaction is negative, the forward reaction happens spontaneously

C  If the equilibrium constant is very large, ΔG is positive

D  Catalysts do not alter the position of equilibrium: they do not shift the equilibrium to the left or right

A  The reaction lies in the middle

B  The reaction lies to the right

C  The reaction lies to the left

A  TRUE

B  FALSE

A  At equilibrium, the concentration of reactants and products stays the same

B  At equilibrium, the rates of the forward and back reactions are identical

C  At equilibrium, there is no net change in the system

D  At equilibrium, the forward and back reactions cease to occur

A  Energy can be neither created nor destroyed

B  The internal energy of the universe is constant

C  When an isolated system undergoes a spontaneous change, the entropy of the system will increase

D  At absolute zero, the entropy of a perfect crystal is considered to be zero

A  The increase in disorder of the system as a reaction proceeds

B  The energy consumed when chemical bonds are broken during a chemical reaction

C  The energy released when chemical bonds are formed during a chemical reaction

D  The difference between the energy released by bond formation and the energy consumed by bond cleavage during a chemical reaction

A  Energy can be converted from one form to another

B  The energy stored in chemical bonds is referred to as kinetic energy

C  An object suspended in the air has more energy than an object lying on the ground

D  The total energy in a chemical universe (a system and its surroundings) is constant

A  FALSE

B  TRUE

A  equilibrium state

B  exergonic change

C  dynamic steady state

D  free-energy change

E  waste of energy

A  anomers

B  cis-trans isomers

C  geometric isomers

D  diastereoisomers

E  enantiomers

A  Trigonal pyramidal

B  Linear

C  Trigonal planar

D  Tetrahedral

E  Trigonal bipyramidal

A  ether

B  carboxylic acid

C  ester

D  aldehyde

E  ketone

A  are independent of the functional groups

B  require an enzyme in all cases

C  are the reactions of the functional groups

D  all of the above

A  open systems

B  thermally isolated

C  closed systems

D  isolated systems

E  none of the above

A  All living organisms try to be in equilibrium

B  A living cell tries to maintain a steady state

C  Maintaining a steady state is coupled to a flux of metabolites

D  Organisms use metabolic processes to obtain the free energy they need to carry out various functions

E  Chemotrophs rely on chemical compounds derived from other organisms

A  N

B  H

C  C

D  O

E  S