link reaction & krebs cycle

where does the link reaction take place ?

mitochondrial matrix

how do you get pyruvate into the mitochondrial matrix ?

active transport

how and where is pyruvate produced ?

• glycolysis

• cytoplasm

steps of the link reactions?

1. pyruvate oxidised to acetate

• 3 carbon pyruvate loses a carbon dioxide and 2 hydrogen molecules

• hydrogens accepted in NAD to make reduced NAD

2. 2 carbon acetate combines with coenzyme A (COA) to form acetylcoenzyme A

overall reaction for the link reaction

pyruvate + NAD + CoA → acetyl CoA + reduced NAD + CO2

why is the link reaction important ?

to oxidise the pyruvate molecules so it can then be turned into acetylcoenzyme to be used in the krebs cycle

what is oxidised in the link reaction ?

the pyruvate is oxidised as it loses a hydrogen

what is reduced in the link reaction ?

the NAD is reduced as it gains a hydrogen

what forms acetylcoenzyme A and where is it deposited ?

• coenzyme A + acetate

• deposited in the krebs cycle

what are the products of the link reaction ?

• acetylcoenzyme

• CO2

• 1x reduced NAD

steps to the krebs cycle ? ????????????????

1. 2 carbon acetylcoenzyme combines with 4 carbon moleule to form 6 carbon molecule

2. series of reactions 6 carbon molecules loses carbon dioxide & hydrogen to form a 4 carbon molecule & one ATP

products of krebs cycle ?

• reduce coenzyme (NAD & FAD)

• 3 CO2

• 1 ATP