MEH: Energy Production: Carbohydrates Flashcards
What is the TCA (tricarboxylic acid cycle) also known as?
Kerbs cycle
What is the role of the TCA cycle in metabolism?
It is the central pathway in the catabolism of sugars, fatty acids, ketone bodies, alcohol and amino acids
It also has an anabolic (biosynthetic) role such as the synthesis of heam, glucose, fatty acids and non-essential amino acids from intermediates.
Where does the TCA cycle occur?
Mitochondria
What does the TCA cycle no function in the absence of?
Oxygen
How is the TCA cycle regulated?
The irreversible steps within TCA are key regulatory steps and are governed by 2 enzymes Isocitrate dehydrogenase and alpha-ketoglutarate dehydrogenase.
These in turn are allosterically inhibited by high energy signals such as NADH and and activated by low energy signals such as ADP.
Oxidative phosphorylation or Substrate level phosphorylation?
Requires membrane associated complexes.
Oxidative phosphorylation
found on the inner mitochondrial membrane
Explain the process of ATP synthesis.
Free energy released in electron transport is used to drive ATP synthesis from ADP+Pi
Name 3 way in which oxidative phosphorylation can be inhibited.
- Inhibition of ETC e.g. CN, CO
- Uncouplers e.g. Fatty acids, Dinitrophenol
- Oxidative/ Phosphorylation diseases
Oxidative phosphorylation or Substrate level phosphorylation?
Can occur to a limited extent in the absence of oxygen.
Substrate level
Oxidative phosphorylation cannot occur at all in the absence of oxygen
Oxidative phosphorylation or Substrate level phosphorylation?
Major process for ATP synthesis in cells requiring a large amount of energy.
Oxidative phosphorylation
Substrate level is a minor process for ATP synthesis
What is oxidative phosphorylation?
When energy is used to drive ATP sysnthesis in the final stage of catabolism.
What is oxidative phosphorylation?
When energy is used to drive ATP synthesis in the final stage of catabolism.
What is p.m.f? (proton motive force)
electrochemical difference due to the greater concentration gradient of protons across the inner mitochondrial membrane.
Which electrons have more energy, NADH or FAD2H?
NADH
What is PDH used for? (Pyruvate dehydrodgenase)
Converting pyruvate into acetyl CoA
