ch 8: energy and enzymes Flashcards
1st law of thermodynamics
energy is neither created, nor destroyed
- it can be transferred or transformed
2nd law of thermodynamics
when energy is converted from one form to another, some of that energy becomes unavailable to do work
why do products have less potential energy than the reactants in biochemical reactions?
due to a release of energy during the reaction
what type of energy is released during the hydrolysis of polymers?
chemical energy
what helps drive the movement of ions through channels?
electrical gradients
what can be released by chemical reactions?
heat
what is captured by pigments?
light energy
what is used in muscle movements?
mechanical energy
metabolism
sum of all biochemical reactions in an organism
catabolic reactions
break down molecules
- example: hydrolysis
anabolic reactions
reactions that build molecules
- example: condensation
exergonic
when G is negative —> energy is released
- spontaneous
endergonic
when G is positive –> energy is consumed
- nonspontaneous
example of endergonic reaction
active transport
example of exergonic reaction
diffusion
if a bond is harder to break, why does it have less potential energy?
energy gets used up because it takes more energy to break the bond
do nonpolar bonds have high or low potential energy?
high
do polar bonds have high or low potential energy?
low
redox reactions
oxidation and reduction
oxidation
loss of electron
reduction
gain of electron
what do redox reactions transfer?
electrons alone or along with protons (H+)
when NAD gets reduced, it becomes
NADH
when FAD2+ gets reduced, it becomes
FADH2
