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Which vitamin is essential for the formation of blood clotting factors?

  1. Vitamin A

  2. Vitamin D

  3. Vitamin E

  4. Vitamin K

The correct answer is: Vitamin K

Vitamin K is essential for the formation of blood clotting factors due to its crucial role in the synthesis of certain proteins that are necessary for blood coagulation. Specifically, Vitamin K is required for the post-translational modification of these proteins through a process known as carboxylation, which enables them to bind calcium ions effectively. This calcium binding is critical for the interaction of clotting factors with phospholipid membranes and contributes to the clotting cascade, a series of biochemical events leading to the formation of a blood clot. Additionally, the deficiency of Vitamin K can lead to increased bleeding tendencies, as the body cannot produce adequate levels of clotting factors II (prothrombin), VII, IX, and X, which are vital for the hemostatic process. Thus, Vitamin K's role in blood clotting is essential, firmly establishing its importance in maintaining vascular integrity and stopping bleeding.