Evaluating The Evidence For Chemiosmosis Flashcards
0
Q
Explain why no ATP is made in mitoblasts (mitochondria stripped of outer membrane)
A
- there is no inter membrane space so H+ ions/protons are not trapped so they do not build up
- so there is no gradient formed and a gradient is needed to make ATP
1
Q
Explain why there is a lower pH in the intermembrane space
A
- inner membrane is impermeable as H+ ions are accumulating
- there is a potential difference across the membrane and the matrix as a loss of H+ from the matrix makes it more negative, a gain of H+ in the intermembrane space makes it more positive
2
Q
Explain why there is no ATP made in the presence of oligomycin (binds to ATP synthase, blocking the channel)
A
- H+ ions cannot flow down the gradient through the ATP synthase channel
- so they cannot produce a proton motive force –> this showed that the flow of H+ ions through ATP synthase was needed to make ATP
3
Q
Explain why no ATP is made of the head pieces are removed from the stalked particles
A
• if there is no heads the cannot rotate under proton motive force to phosphorylate ADP + Pi –> heads make ATP