Question

The main function of white blood cells is

• A. To help red blood cells in the transportation of oxygen and carbon dioxide.
• B. To clot the blood at the time of injuries
• C. To accelerate the production of red blood cells in the bone marrow
• D. To defend the body against infections

Answer 1

The correct option is D

To defend the body against infections

The correct option is option D.

Explanations for the correct option:

1. White blood cells are also referred to as leukocytes and form a major part of the immune system.
2. The granulocytes respond to allergic reactions and take part in providing the general immune response in the body.
3. They also function as scavengers and destroy foreign bacteria and fungi detected in the body.
4. Lymphocytes recognize and remove infected cells. It participates in antibody production to eradicate infections.

Explanations for the incorrect options:

Option A:

1. Red blood cells are flattened round cells that are produced in the bone marrow and contain hemoglobin.
2. Hemoglobin is a protein that is present in red blood cells and the iron present in them binds to oxygen and helps in their transportation.
3. The normal range of hemoglobin is 13.8-17.2 g/dL in males and 12.1-15.1 in females.

Option B:

1. Platelets are blood cells that play a key role in promoting the clotting of blood.
2. A healthy platelet count ranges from 150000 to 450000 platelets per microliter.

Option C:

1. Erythropoietin is a hormone that stimulates the bone marrow to synthesize new red blood cells.
2. It initiates red blood cell formation and promotes the synthesis of hemoglobin molecules.

Final answer: The main function of white blood cells is to defend the body against infections.