3.5.2 RESPIRATION

1. Glycolysis
2. Link reaction
3. Krebs cycle
4. Oxidative phosphorylation

molecules that aid enzymes by transferring chemical groups(eg hydrogen) from one molecule to another

1)Glucose is phosphorylated by 2 ATP
2)Phosphorylated glucose splits into two triose phosphates
3)The two triose phosphates are each oxidised by a NAD and produces 4 ATP. Forming 2 pyruvates

- 2 Pyruvate
- 2 NADH
- Net 2 ATP

-Pyruvate and NADH are actively transported from cytoplasm to mitochondrial matrix
1)Pyruvate is oxidised by a NAD and releases a CO2. Making Acetate
2)Acetate combines with coenzyme A to form acetyl coA
This happens twice.

- 2 acetyl coA
- 2 CO2
- 2 NADH

1)Acetyl coA reacts with oxaloacetate(4C) to form Citrate(6C) and releases enzyme coA.
2)Citrate is decarboxylated twice, oxidised four times thrice by NAD and once by FAD and produces an ATP by substrate level phosphorylation . Producing oxaloacetate again
THIS IS DONE TWICE
remember order of oxidised/decarboxylated by DE NA DE NA A FA NA

- 6 NADH
- 4 CO2
- 2 FADH
- 2 ATP

To produce NADH AND FADH

1) NADH and FADH donate the electrons of the hydrogen atoms to first protein in the electron transport chain
2)The electrons pass along the the electron transport chain carriers by redox reactions
3)This releases enough energy to actively transport the H+ into the intermembrane space
4)This forms a gradient in which the H+ ions now FD down thru ATP synthase which catalyses the production of ATP from ADP + Pi . This is called CHEMIOSMOSIS

It combines with the electrons and H+ ions to form H20.
It is the final electron acceptor

Glycolysis happens then pyruvate oxidises NADH forming lactate. So NAD can be used for glycolysis AGAIN
Same is plants except forms ethanol + CO2