Which of the following vitamin helps in blood clotting in humans?
- (a)Vitamin A
- (b)Vitamin B
- (c)Vitamin K
- (d)Vitamin D
Correct — C, Vitamin K. Vitamin K is essential for synthesising several clotting factors in the liver (including prothrombin, Factor II), which the blood-clotting cascade needs to stop bleeding. Without adequate Vitamin K, blood fails to clot properly, causing prolonged bleeding.
- (a)Vitamin A — Vitamin A supports vision, immune function and epithelial health — it plays no role in the clotting cascade.
- (b)Vitamin B — The B-complex vitamins support energy metabolism, nerve function and red blood cell formation — none of them are required for clot formation.
- (d)Vitamin D — Vitamin D regulates calcium and phosphorus absorption for bone health — it is not the clotting vitamin (though calcium itself is a co-factor in the clotting cascade, separate from Vitamin D's main role).
Vitamin K (from Latin 'Koagulation') is a fat-soluble vitamin required by the liver to produce clotting factors II, VII, IX and X. It exists as K1 (phylloquinone, from green leafy vegetables) and K2 (menaquinone, made by gut bacteria). A deficiency causes easy bruising and prolonged bleeding, which is why newborns are routinely given a Vitamin K injection at birth.
The exam trap is confusing the fat-soluble vitamins (A, D, E, K) by function — students often default to Vitamin D (bone-linked, most commonly discussed) or Vitamin A when asked a vitamin-deficiency-disease question. Anchoring the mnemonic 'K = Koagulation = clotting' avoids the mix-up.
- Vitamin K is required for liver synthesis of clotting factors II (prothrombin), VII, IX, and X
- Vitamin K1 (phylloquinone) comes from green leafy vegetables; Vitamin K2 (menaquinone) is made by gut bacteria
- Vitamin K deficiency causes easy bruising and prolonged bleeding
- Vitamin K is fat-soluble, along with Vitamins A, D and E
- Confusing Vitamin K's clotting role with Vitamin D's bone/calcium role
- Assuming Vitamin C (linked to wound healing generally) is the clotting vitamin
MPPSC and other state PCS exams frequently ask 'which vitamin is responsible for X function/deficiency disease' in a direct one-line format — memorise the vitamin-function-deficiency triplet for each of A, B, C, D, E, K.
No directly related past PYQ was found.
- practice — not a real PYQ
Vitamin K is essential for the synthesis of which of the following clotting factors in the liver?
- (a)Fibrinogen only
- (b)Prothrombin (Factor II) and related factors
- (c)Platelets
- (d)Haemoglobin
Answer(b) Prothrombin (Factor II) and related clotting factors (VII, IX, X) — synthesised in the liver with Vitamin K.
- practice — not a real PYQ
A deficiency of which vitamin leads to night blindness in humans?
- (a)Vitamin A
- (b)Vitamin B12
- (c)Vitamin K
- (d)Vitamin E
Answer(a) Vitamin A — its deficiency impairs the eye's ability to adapt to low light, causing night blindness.