Given below are sets of five terms each. Rewrite the terms in correct order in a logical sequence. Example: Large intestine, Stomach, Mouth, Small intestine, Oesophagus. Answer: Mouth → Oesophagus → Stomach → Small intestine → Large intestine.
Fibrin, Platelets, Thromboplastin, Fibrinogen, Thrombin.
Topic: Blood clotting sequence
Answer
Platelets → Thromboplastin → Thrombin → Fibrinogen → Fibrin
This is the CLOTTING CASCADE, and it runs in a fixed order: PLATELETS break at the wound and release THROMBOPLASTIN thromboplastin, with CALCIUM and vitamin K, converts prothrombin into THROMBIN thrombin converts soluble FIBRINOGEN into insoluble FIBRIN, whose threads form the mesh of the clot
NOTE THE PAIRS, which make the order easy to reconstruct: prothrombin → thrombin, and fibrinogen → fibrin. In each case the LONGER name is the INACTIVE precursor and the SHORTER the ACTIVE form. So fibrinogen must come before fibrin.
A failure anywhere in this chain causes HAEMOPHILIA, in which the blood does not clot.