Use Fig. 2 (p. 462) to distinguish between catabolic and anabolic
pathways. Correct Answer-Catabolic Pathways: Breakdown
macromolecules into smaller components and release chemical energy
Anabolic pathways: combining small molecules into larger ones and
requiring an input of energy
DG(deltaG) = DH(deltaH) - TDS(deltaS)
Name and define each of the terms in the above equation Correct
Answer-DS= change in free energy; total energy in a system that can do
work at constant temperature and pressure
neg=spontatneous(exergonic)/ pos=nonspontaneous(endergonic)
DH= change in enthalpy. The heat content of a system
neg=exothermic... releases heat/ pos=endothermic...absorbs heat
DS=change in entropy. Measure of disorder in a system
More entropy means more disorder
Distinguish between DG, DG°, and DG'° Correct Answer-DG= change
in free energy in a given reaction
, DG°=standard change in free energy at 298K, 1M, 1atm
DG'°= standard change in free energy under biological conditions
(everything plus cncentration of water (55.5M) and at pH=7).
What is the sign of DG'° when the reaction proceeds in the written
direction Correct Answer-Negative
Compare the free energy content of acid anhydride and ester bonds.
Correct Answer-Acid anhydrides have much higher free energy content
than ester bonds
Which term in the Gibbs equation can be used to predict whether a
reaction will proceed? Correct Answer-∆G... it's sign will tell if if the
reaction is spontaneous or not. Spontaneous=negative. It will proceed.
∆G = ∆G'° + RT ln ([C][D] / [A][B]) Correct Answer-Gibbs Equation
What does DG tell you about the rate of the reaction? Correct Answer-
Nothing. K tells us this.
What effect do enzymes have on DG Correct Answer-None
Draw the structure of ATP Correct Answer-