MCQ Detailed View

The vitamin that helps in clotting of blood is Vitamin K. It plays an essential role in the production of clotting factors, which are special proteins required to stop bleeding when a blood vessel is injured. Without vitamin K, the blood would not clot properly, leading to excessive bleeding even from minor cuts or injuries.Vitamin K is a fat-soluble vitamin naturally found in two main forms:

1. 
   

   Vitamin K1 (phylloquinone): Found mainly in green leafy vegetables like spinach, kale, and broccoli.

   
   


2. 
   

   Vitamin K2 (menaquinone): Produced by certain gut bacteria and found in some animal-based and fermented foods.

   
   

When an injury occurs, platelets in the blood gather at the wound site to form a temporary plug. At the same time, clotting factors activated by Vitamin K trigger a complex chemical reaction that strengthens this plug with fibrin threads, stopping further blood loss. A deficiency of vitamin K can lead to delayed clotting, frequent nosebleeds, heavy menstrual bleeding, or severe hemorrhage in serious cases.

Explanation of other options:

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  Vitamin B1 (Thiamine): Helps in energy metabolism but not in clotting.

  
  


• 
  

  Vitamin B2 (Riboflavin): Important for enzyme functions but unrelated to clotting.

  
  


• 
  

  Vitamin D: Helps absorb calcium and maintain strong bones but has no direct role in clot formation.

  
  

Newborn babies are often given a Vitamin K injection shortly after birth to prevent bleeding disorders, as their natural stores are low at birth.

In conclusion, Vitamin K is essential for the clotting of blood, making option D (Vitamin K) the correct answer for this biology MCQ.