"Basics"
True/false: Respiration conserves more energy than fermentation.
TRUE.
(Why?)
True/false: Oxygen is required for glycolysis.
False. (This is known as a ____ pathway.)
True/false: In fermentation, glucose is fully oxidized to CO2.
False.
True/False: During the TCA cycle, carbon is fully oxidized to CO2.
True.
(What form of carbon?)
oxidative
Regulation allows cells to balance ____ with _____.
anabolism; catabolism
After glycolysis, NAD+ is regenerated by _____ or _______.
Respiration or fermentation.
___ is converted to ____ during glycolysis.
Glucose; pyruvate
(Is this process catabolic or anabolic?)
True/False: fermentation requires an external electron acceptor
False
(What is the electron acceptor?)
True/false: In heterotrophs, glycolysis & the TCA cycle both generate energy and build ALL of the building blocks cells need.
True.
During oxidative phosphorylation, electrons are transferred from reduced coenzymes to electron ____ in order of ______ reduction potential.
acceptors; decreasing
Describe the 2 main regulation strategies:
amount of enzyme present; enzyme activity
There's a step between glycolysis and the TCA cycle... What is it?
pyruvate must be oxidatively decarboxylated to acetyl-CoA
Glycolysis generates ATP using the mechanism __________.
substrate-level phosphorylation
In fermentation, oxidized organics are reduced by NAD_, regenerating NAD_.
H; +
Can compounds enter/exit the TCA cycle at intermediate stages? Why?
Yes. This is very convenient, since various intermediates can be used to synthesize cellular building blocks.
Glycolysis and TCA cycle are both _____________ phosphorylation; electron transport is _________ phosphorylation
Substrate-level; oxidative
What type of inhibition is represented in Slide 2?
Feedback inhibition
The diagrams on Slide 1 represent two different mechanisms; what are they?
oxidative phosphorylation (bottom)
How is the energy gained from glycolysis stored?
used to form high energy P bonds to generate ATP
If glucose is NOT fully oxidized to CO2 during fermentation, what does this mean energetically?
No ATP is produced by fermentation... it is only used to regenerate NAD+!
Walk us through Slide 3. How many of each are produced?
CO2, ATP, NADH, FADH2
3 CO2
1 ATP
4 NADH
1FADH2
As electrons are transferred, protons are also transferred, resulting in a voltage and pH gradient. How is this energy dissipated?
ATPase uses the energy of protons flowing back into the cell to form ATP from ADP and Pi.
(What is the voltage/pH gradient called?)
Describe covalent modification
regulation is mediated by compounds not related to the pathway, which allows cells to regulate several different enzymatic pathways with the same compound