W5- Lecture 26- Oxidative phosphorylation

Question 1

describe action on complex 1

Answer 1

Complex 1 receives electron from NADH which is converted to NAD+
Electron passed through complex
Co enzyme Q 10 becomes reduced
Protons are pumped into the inter membrane space

Question 2

describe action on complex 2

Answer 2

Complex 2 (not a proton pump like C1)
FADH2 feeds into complex 2
Electrons from oxidation of succinate to fumarate
Co enzyme Q10 (lipid soluble) reduces and carry’s electrons

Question 3

describe action on complex 3

Answer 3

Complex 3
Co enzyme q 10 transfers its electrons to complex 3
Electrons pass through complex 3 to cytochrome c which is an electron shuttle(to complex 4)

Question 4

describe action on complex 4

Answer 4

Complex 4
Cytochrome c becomes oxidised passing electros to complex 4
Limited proton pumping
Electron passed to oxygen as final electron acceptor producing water
now gradient of protons

Question 5

in which direction do the electrons flow / why ?

Answer 5

1 -2-3-4
at each stage electron acceptor has change in reduction potential
can run in reverse in adverse conditions

Question 6

describe action on complex 5

Answer 6

complex 5 (F1F0 synthase )
Hydrogen ions move back down the concentration gradient
And drive synthesis of ATP
Rotary movement of complex