<prompt> Which of the following statements is not true for heparin -Acts by activating anti-thrombin IIIProtamine sulphate antagonizes its actionRequires aPTT monitoring in patientHas only in vivo anticoagulant action  <response>: Ans. is d i.e., Has only in vivo anticoagulant action o Heparin has action both in vitro and in vivo. 