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` Used to generate NADPH and specialized productsneeded by the cell.

` Also known as:

1. Hexose monophosphate shunt.

2. Phosphogluconate pathway.

`

Operating in two phases:1. Oxidative phase.

2. Non-oxidative phase.

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1. Used for production of NADPH (the universal reductant

in anabolic pathways) from NADP.

2. Used for the production of ribose for nucleotide andnucleic acid synthesis.

3. Acts as a connection route between different pathways.

- allows the entry of some carbohydrates into the

glycolytic pathway.

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Glucose6 phosphateglucose6

phosphate dehyrogenase

6phosphogluconolactonegluconolactone hydrolase

6phosphoglocunate6

phosphoglocunate dehydrogenase

Ribulose5phosphatephosphopentose isomerase

Ribose5phosphate

NA

DP+

NADPH+H+

NADP+

NADPH

dehydrogenation

dehydrogenation

isomerisation

CO2 +

H2OH+

hydrolysis

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`

Oxidative phase Reactions produce NADPH Irreversible reaction3Glucose-6-phosphate + 6NADP+ 3 ribose-5P + 3CO2 +

6NADPH + 6H+

` Non-Oxidative phase

Produces 2-Fructose-6-Phosphate and Glyceraldehyde -3-Phosphate. Reversible reactions feed to glycolysis

2 Xylulose-5P + ribose-5P 2 Fructose-6P + Glyceraldehyde-3P

The sum of these two phases:

3Glucose-6-phosphate + 6NADP+ 2 Fructose-6P +Glyceraldehyde-3P + 3CO2 + 6NADPH + 6H+

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