chapter9-cellular-respiration Flashcards
(20 cards)
Glycolysis
net inputs, net outputs
net input: 2ADP, 2NAD+, 1 Glucose
net output:2ATP, 2NADH, 2 Pyruvate
Acetal CoA formation or Pyruvate oxidation
net inputs, net outputs
net input: NAD+, pyruvate, coenzyme A
net output: 1 acetyl CoA, 1 NADH, 1CO2
times: 2 (for each pyruvate)
Citric acid cycle or Krebs cycle
net inputs, net outputs
net input: ADP, NAD+, acetyl CoA
net output: coenzyme A, 2 CO2, 3 NADH, 1 ATP, 1 FADH2
times: 2 (for each acetyl CoA)
Oxidative Phosphorylation
net inputs, net outputs
net input: NADH, FADH2, ADP, O2
net output: NAD+, FAD, ATP, H2O
3 ATP for NADH
2 ATP for FADH2
List the location at which the following occurs:
Glycolysis
acetyl CoA Formation (pyruvate oxidation)
citric acid cycle (Krebs cycle)
oxidative phosphorylation (electron transport chain + chemiosmosis)
Glycolysis: cytosol
acetyl CoA: matrix
citric acid cycle: matrix
oxidative phosphorylation: inner mitochondrial membrane
In glycolysis,
what compound becomes oxidized?
what compound becomes reduced?
oxidized: glucose -> pyruvate
reduced: NAD+ -> NADH
What is the electron acceptor in glycolysis?
NAD+, it becomes NADH
What products contain energy that can be used by other biological reactions in “glycolysis”?
pyruvate, ATP, NADH
What happens to pyruvate in pyruvate oxidation?
It becomes a 2Carbon molecule called acetal CoA and releases CO2.
Why during the Krebs cycle does acetal CoA (2 Carbon) need to be combined with a 4 Carbon?
It is easier to remove electrons and produce CO2 from compounds with three or more carbons.
In anaerobic conditions, what happens to the oxidative phosphorylation stage?
both ATP synthesis and the electron transport chain stop.
What is the final electron acceptor in oxidative phosphorylation?
Oxygen
During the electron transport chain, which complexes pump protons into the intermembrane space from the matrix?
1,3,4
complex 2 has no electron pump.
What is the mobile electron carrier that transports electrons from complex 1 to complex 3?
Coenzyme Q or CoQ
What is the mobile electron carrier that transports electrons from complex 3 to complex 4? Where do the electrons end up?
Cytochrome C or CytC. The electrons end up with the final electron acceptor, oxygen; and they produce (2) water.
Which increases the gradient concentration of H+ more, NADH or FADH2?
NADH, b/c FADH2 is reduced at complex 2, and there’s no pump at complex 2.
What is gramicidin? And what is its purpose in oxidative phosphorylation?
It is an inhibitor and it creates a channel through the membrane where H+ (protons) can travel. This causes the H+ concentration in the intermembrane space to be reduced and more closely match the concentration in the matrix. As a result, ATP synthesis decreases, but the electron transport chain stays unaffected.
What is the equation for cell respiration (overall equation)?
C6H12O6 + 6O2 –> 6CO2 + 6H2O + ATP
glucose + oxygen –> carbon dioxide + water + energy
In anaerobic reactions (no oxygen), what stops the conversion of pyruvate to acetal CoA?
Since there is no oxygen, the electron transport chain stops. This in turn prevents the reduction of NADH to NAD+, a key ingredient to convert pyruvate to acetal CoA.
What does ATP inhibit and in turn causes the production of ATP to slow / stop?
phosphofructokinase (PFK)
too much ATP inhibits this, and thus limits the production of ATP to a certain number.
