AS OCR Biology: Oxidative Phosphorylation and Chemiosmosis

Oxidative Phosphorylation and Chemiosmosis

The final stage of aerobic respiration:
Oxidative Phosphorylation
It takes place within the intermembrane space of the mitochondria, where there
are cristae increasing the surface area for electron carriers and ATP synthase.
Reduced NAD and FAD, from the Krebs cycle, are oxidised when they donate
hydrogen…

Electrons flow along the electron transport chain. This provides energy for the
active transport of protons(Chemiosmosis)
NADH




Dehydrogenas Protein II CARRIER Protein III CARRIER Cytochrome ATP
e (Intrinsic) (Extrinsic) Ubiquinone (Intrinsic) Cytochrome C Oxidase Synthase
(2e- per go) (1e- per go) (intrinsic) (intrinsic)

1. NADH oxidised at NADH Dehydrogenase
1.1.…

In Oxidative Phosphorylation,
On average, for every NADH molecule, 2.5 ATP molecules are produced.
On average, for every FADH molecule, 1.5 ATP molecules are produced.

Stages of
Name of Molecule Total ATP
Respirati produced
on
Glycolysis Link Krebs
Reaction Cycle
NADH 2 2 6 10 x 2.5 = 25
FADH…

as it's positively charged and can pass through ion specific channel proteins. The same case
happens with Aspartate.


Questions
1. Oxygen is the final molecule the electrons bind to and are stable. This then is the end of
oxidative phosphorylation, and so respiration.
2. The proton gradient produces a pH…