Aerobic Metabolism Flashcards
What are the major co-enzymes in most cell redox redactions?
FAD and NAD+
FAD can accept 2 H to become FADH2
NAD+ can accepts 1H to become NADH
Redox reactions are the molecular basis for energy generation in the cell
Briefly describe an overview of the citric
Acid cycle
The citric acid cycle involves a number of oxidation-reduction reactions where the function is to harvest electrons from carbon fuels
The carbon compounds can be oxidised and lose electrons
What is formed from the TCA cycle?
Forms NADH and FADH2 and removes electrons
What is considered the first step of the TCA cycle?
A 4 carbon compound (oxaloacetate) condenses with a 2 carbon acetyl unit to yield a 6 carbon tricarboxylic acid (citrate)
What is considered the 2nd step of the critic acid cycle?
Citrate (6 carbons) is oxidatively decarboxylated to a 5 carbon compound (alpha-ketoglutarate)
At this step a CO2 and NADH2 given off
What is considered step 3 of the citric acid cycle?
The 5 carbon compound is decarboxylated to 4 carbons (succinate)
At this step another CO2 and NADH2 is given off
What is the final step (bottom part) of the TCA cycle?
Succinate (4 carbons) converted to Malate (4 carbons)
An FADH2 and a GTP (ATP) given off
Where does Krebs cycle occur
All in mitochondria
Explain the change in carbon and electrons in the TCA cycle
2 carbons enter and 2 carbons leave in the form of CO2 (step 2+3)
6 electrons are converted to 3 molecules of NAD+ (step 2,3,5)
2 electrons are transferred to one molecule of FAD (step 4)
What do NADH and FADH2 do in respect to the electron transport chain ?
They carry hydrogen atoms which are oxidised via the ETC
This allows the oxidative phosphorylation of ADP+Pi->ATP
When are oxidative phosphorylation electrons released?
In the reoxidation of NADH and FADH2
The electrons flow through a series of membrane proteins which creates a proton gradient H+
These protons then flow through ATP synthase to generate ATP from ADP+Pi
How do electrons obtained from food have an effect in the ETC?
They will transferred to NAD and FAD to form NADH and FADH2
They are then transferred to oxygen in the inner membrane of the mitochondria where the o2 is reduced to water
What do complex I-IV do?
They pass an electron along and put protons across the membrane
What is complex V
The ATP synthase
What are the other carriers involved in the ETC?
Q (ubiquitin) and C (cytochrome C)
