Clinical aspects of electron transport

Question 1

How does cyanide effect the electron transport chain

Answer 1

CN- prevents acceptance of electrons by oxygen

so prevents the rre-oxiidation of reducing equivalents

Question 2

Explain the effect of uncouplers on oxidative phosphorylation

Answer 2

Increase the permeability of the inner membrane to protons, so reduces the PMF so reduces ATP synthesis

Question 3

Describe genetic Ox/Phos diseases

Answer 3

Genetic defects in proteins encoded by DNA (Eg. the Proton translocating complexes and the ATP synthase

You get reduced electron transport and ATP synthesis

Question 4

Explain how brown adipose tissue responds to cold

Answer 4

Noradrenaline activates lipase that releases FAs from TAG
FA oxidised to NADH/FADH2–>electron transport
FAs also activate UCP1 (Thermogenin)
Thermogenin transports protons back into the mitochondria

This means that the electron transport is UNCOUPLED from the ATP synthesis
Energy from Proton motive force instead used for heat