Chapter 7, Problem 12TY

Summary Introduction

Introduction:

Hemostasis refers to the cascade of mechanisms that works for stopping the excessive bleeding due to any injury to the blood vessels. This happens by coagulating the blood, that is, converting the liquid form of blood into the gel form. The blood inside our blood vessel is always protected from being coagulated due to the presence of thrombomodulin. It is a substance similar to heparin that prevent the blood coagulation and its aggregation to form clots.

Correct answer:

Steps starting from the damage to the blood vessels and aggregation of platelets to the formation of clot is the whole process of hemostasis.

Justification/ Explanation for the correct answer:

Option (b) is given that the process of hemostasis starts with the injury to some blood vessel that leads to the bleeding and thus, activation of clotting cascade. The platelets group together at that site to form a plug, then the activation of prothrombin occurs and thrombin is formed. Then fibrin is formed from fibrinogen eventually forming a clot at the site of injury to control excessive bleeding. Hence, option (b) is correct.