All Exams Test series for 1 year @ ₹349 only
Question

Which vitamin activates proteins and calcium essential for blood clotting?

This question was previously asked in
RRB NTPC 2019 CBT 1 Question Paper (8-Mar-2021) (Shift 2)
The correct answer is
Vitamin K

Vitamin K Function in Blood Clotting

The question asks which vitamin activates proteins and calcium, which are essential for blood clotting. This process is also known as coagulation.

Vitamin K's Role

  • Vitamin K plays a crucial role in the synthesis of several proteins required for blood coagulation.
  • It acts as a cofactor for the enzyme gamma-glutamyl carboxylase, which modifies specific clotting factors (specifically factors II, VII, IX, and X).
  • This modification, called gamma-carboxylation, enables these proteins to bind calcium ions ($Ca^{2+}$).
  • The binding of calcium ions is a critical step that allows these clotting factors to assemble on cell surfaces and initiate the coagulation cascade, leading to the formation of a blood clot.

Why Other Vitamins Are Incorrect

  • Vitamin D primarily regulates calcium and phosphate homeostasis, aiding calcium absorption in the gut, but doesn't directly activate clotting proteins.
  • Vitamin C is an antioxidant and is essential for collagen synthesis, playing a role in the integrity of blood vessels, but not directly in activating clotting factors.
  • Vitamin B1 (Thiamine) is involved in carbohydrate metabolism and nerve function, having no direct role in blood clotting activation.

Therefore, Vitamin K is the specific vitamin that activates the proteins and calcium needed for effective blood clotting.

Was this answer helpful?

Similar Questions

  1. When respiration takes place even in the absence of oxygen, it is called ______ respiration.
  2. Rakesh donates blood twice in 3 years each time 330 ml. How many litres of blood will he donate in 6 years?
  3. What is the scientific name of the fruit 'mango'?
  4. Involuntary actions such as breathing, salivation and peristalsis are controlled by the:
  5. Name an enzyme used for the conversion of proteins into a peptide.
  6. Synapse is the point at which a nervous impulse passes from:
  7. Penicillium is a/an _______.
  8. Which of the following vitamins is rich in yeast?
  9. The animals that eat both plants and animals are called:
  10. Which of the following animals has a three-chambered heart?

Important Questions from Biology

  1. Which of the following statements about living and non-living being is/are correct?

    1. While living being can demonstrate growth and repair, non-living being cannot.

    2. While living being demonstrates metabolic processes, non-living being does not.

    Select the correct answer using the code given below.
  2. Movement of materials to different parts of cytoplasm and nucleus is generally carried out by

  3. The gaseous product of a process in plants is a requirement for another vital process that releases energy. Given below are four combinations of the process and product. Identify the correct answer.

  4. Which one of the following cell organelles may play a role in expelling excess water and wastes in case of unicellular organisms?

  5. Transformation of meristematic cells into specific permanent tissues occurs by the process of

Need Expert Advice?
Upcoming Exams
RRB ALP
July 28, 2026
RRB Group D
August 03, 2026
Test Series
RRB NTPC img
Railways
RRB NTPC Under Graduate 2026 New Mock Test Series
1459 Tests 2 Tests Free
216 Attempts
4.3(512)
English, Hindi, Telugu +7 More

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App