Lecture 10 DA Flashcards
What is the outer membrane of the mitochondria very similar to?
The cell membrane.
What is the inner membrane of the mitochondria like?
Stiff, waxy and inflexible.
What does the inner membrane of the mitochondria have, similar to bacteria?
Has the bacterial equivalent of one of the three major phospholipids in normal cell membranes.
Why is the mitochondria a lot like bacteria?
Has its own genome, which is circular.
Has bacteria-like promoters, no introns, and bacterial ribosomes.
What fuel does the CNS prefer?
Glucose.
What fuel does the heart prefer?
Ketone bodies.
Can the CNS use anything aside from glucose?
Yes, ketone bodies, but only in severe cases.
Why does the TCA cycle go fast?
It is able to reoxidise the reduced oxaloacetate.
Where is oxaloacetate formed?
In the matrix, by carboxylation of pyruvate.
What does oxaloacetate exit the mitochondria as, and what happens there?
Exits as malate, and is reoxidised to oxaloacetate in the cytosol.
How can glycerol be used in the TCA cycle?
Can be phosphorylated to become an intermediate of the TCA cycle - phosphoglyderaldehyde.
How is fat oxidised?
Acyl chains need β oxidation.
What is needed for β oxidation?
Activated by coenzyme A.
What is β oxidation used for, and what is a product of it? where is this product used?
Reduces 2 molecules of NAD+ and 1 FAD+. Acetyl-CoA is a product, repeating until acetyl-CoA runs out. They are used in the TCA cycle.
Where is the energy needed to drive ATP synthesis obtained from?
Reoxidation of FADH2 and NADH.
What is the pH of the inner membrane space and the maxtrix?
Matrix - 7
Inner membrane space - 2.5
Are reactions that release gas reversible?
Likely to be irreversible.
What is the activators and inhibitors of the TCA cycle?
Activated by ATP
Inhibited by acetyl-CoA and NADH
Feedback inhibition by GTP
How much H+ is pumped from one NADH?
10H+.
What is the pumped H+ spent by?
ATP synthase, which phosphorylates ADP, using the H+ potential.
How much H+ is required for one ATP?
3H+.
