Cytokinin biosynthesis, catalyzed by isopentenyl transferase (IPT), is the addition of the isopentenyl side chain from DMAPP (dimethylallyl diphosphate) to an adenosine moiety (ATP or ADP). iPRTP or iPRDP is converted to ZTP or ZDP respectively by cytochrome P450 monooxygenase (CYP735A) and eventually is converted to zeatin.

TLS Online TPP Program

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#Unit 7. System Physiology – Animal

Active factor XII then activates  factor XI, & active factor XI activates factor IX.

TLS Online TPP Program

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#Unit 7. System Physiology – Animal

Activated factor IX forms a complex with active factor VIII, which is activated when it is separated from von Willebrand factor.

TLS Online TPP Program

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#Unit 7. System Physiology – Animal

The complex of IXa and VIIIa activate factor X. 

TLS Online TPP Program

#Id: 5193

#Unit 7. System Physiology – Animal

Phospholipids from aggregated platelets and Ca2+ are necessary for full activation of factor X.

TLS Online TPP Program

#Id: 5194

#Unit 7. System Physiology – Animal

Factor X can be activated by either of two systems: Intrinsic system Extrinsic system

TLS Online TPP Program

#Id: 5195

#Unit 7. System Physiology – Animal

The extrinsic system is triggered by the release of tissue thromboplastin, a protein–phospholipid mixture that activates factor VII.