Ch. 6 Energy and Metabolism Flashcards
What is Thermodynamics?
a branch of chemistry concerned with energy changes
What’s energy?
the ability to do work
What’s kinetic energy?
energy of motion
What’s potential energy?
stored energy
What is heat?
a measurement of energy in calories
What’s the 1st law of thermodynamics?
energy can only be converted
What’s the second law of thermodynamics?
energy can be lost only as heat
What’s the free energy equation?
G=H-TS
g: energy available to do work
h: enthalpy, total energy in a molecules chemical bond
t: absolute temperature in kelvin
s: entropy, unavailable energy
What’s delta (triangle shape) G?
change in free energy
Positive delta G has _____ free energy than reactants while negative delta G has _____ free energy than reactants.
more, less
Which of the two has positive delta G? Endergonic or Exergonic?
Endergonic
Which of the two has negative delta G? Endergonic or exergonic?
Exergonic
What does a catalyst do?
lowers activation energy level
How many phosphates does ATP and ADP have?
ATP = 3
ADP = 2
What drives endergonic reactions?
ATP hydrolysis
What is anabolism/ anabolic reactions?
expend energy to build up molecules
What’s catabolism/catabolic reactions?
harvest energy by breaking down molecules
What’s bioenergetics?
analysis of how energy powers the activities of living systems
What’s free energy?
the energy available to do work at a constant temperature in a system
What’s Gibbs free energy (G)?
constant temperature, volume and pressure
What’s enthalpy (H)?
g = to the Total energy in a molecules chemical bond
What’s the formula for Kelvin?
K = C+273
What’s the formula for change in free energy?
Delta G = Delta H - T Delta S
Does negative or positive Delta G occur spontaneously?
Negative Delta G
How much phosphate does AMP have?
one
What’s a substrate?
molecules that undergo reactions
What’s metabolism?
collection of all chemical reactions
What’s an induced fit?
when an enzyme is altered to fit a substrate
What are ribozymes?
RNA catalysts
Who do intramolecular catalysis’ catalyze?
themselves
Who do intermolecular catalysis’ catalyze?
other molecules
What impacts the enzyme-catalyzed reactions?
- concentration of substances and enzymes
- temperature and pH
- inhibitors
-activators
What’s a biological pathway?
sequences in which products of one reaction become the substrate for the next
What’s feedback inhibition?
when the final product In a sequence goes back to the first enzyme and binds to it’s allosteric site to regulate the biological pathway
What’s an allosteric activator?
something that binds to the allosteric site to keep an enzyme in active mode… increases enzyme activity
