Same chapter3 marksDifficulty: Medium
Describe the conducting system of the human heart.
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3 marksDifficulty: Medium
What is the coagulation of blood and what is the role of platelets in it?
Original Khojo Papers practice question — not from a past board paper.
Answer
Coagulation is the conversion of liquid blood into a gel that seals a wound. Injured tissue and platelets release thromboplastin, which with calcium ions converts prothrombin into thrombin; thrombin then converts soluble fibrinogen into insoluble fibrin threads that trap blood cells and form the clot.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Platelets also plug the wound physically before the clot forms.
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