Question

Mark the pair of substances among the following which are essential for coagulation of blood.

• A. Heparin and calcium ions
• B. Calcium ions and platelet factors
• C. Oxalates and citrates
• D. Platelet factors and heparin

Answer 1

The correct option is B

Calcium ions and platelet factors

Explanation of the correct option:

The correct option is B:

1. The process of formation of a clot in the blood is known as blood coagulation.
2. Blood clotting occurs at the time of an injury or infection to prevent the loss of blood by stopping the blood flow.
3. Platelets or thrombocytes are responsible for blood coagulation.
4. Calcium ions are involved in the process of blood coagulation by converting thromboplastin and platelet factors into prothrombinase and prothrombin into thrombin.

Explanation of the incorrect options:

Option A:

1. Heparin is an anticoagulant that inhibits coagulation inside the blood vessel.
2. But calcium ions help in coagulation.

Option C:

1. Oxalates and citrates are treated as anticoagulants when the blood is taken outside the body and treated in test tubes.

Option D:

1. Platelet factors help in coagulation.
2. But heparin inhibits coagulation of blood.