Which statement accurately describes the interactions between the molecules thrombin, antithrombin, and heparan sulfate?
A) In the absence of heparan sulfate, antithrombin binds tightly to thrombin, inhibiting blood coagulation.
B) In the absence of heparan sulfate, antithrombin cannot bind to thrombin, inhibiting blood coagulation.
C) In the presence of heparan sulfate, antithrombin binds tightly to thrombin, inhibiting blood coagulation.
D) In the presence of heparan sulfate, antithrombin cannot bind to thrombin, enabling blood coagulation.
E) In the presence of heparan sulfate, antithrombin binds tightly to thrombin, enabling blood coagulation.

Question

Quizplus · Accepted Answer

Heparan sulfate acts as a cofactor to increase the binding affinity between antithrombin and thrombin. In the presence of heparan sulfate, antithrombin binds tightly to thrombin, inhibiting blood coagulation. Without heparan sulfate, the binding affinity between antithrombin and thrombin is substantially reduced, resulting in an inefficient inhibition of blood coagulation.

Which Statement Accurately Describes the Interactions Between the Molecules Thrombin