Which of the following is the fluid part of the blood?

Question

Which of the following is the fluid part of the blood?

1. A. WBC
2. B. Plasma (Correct answer)
3. C. Blood platelets
4. D. RBC

Correct Answer

Option B — Plasma

Detailed Solution & Explanation

The correct answer is Plasma.

Key Points

• Plasma is the fluid (liquid) part of blood. It is a pale-yellow liquid that makes up about 55% of the total blood volume and is roughly 90-92% water, with the rest being proteins (albumin, globulin, fibrinogen), salts, nutrients, hormones and waste products.
• Plasma acts as the medium that transports blood cells, nutrients, hormones and waste around the body.
• The other components are the formed (cellular) elements suspended in this plasma: RBCs (red blood cells) carry oxygen, WBCs (white blood cells) fight infection, and platelets help in blood clotting.
• Since the question asks for the fluid portion, the answer is Plasma, option (B).

Additional Information

• Blood is about 55% plasma and 45% formed elements (RBCs, WBCs, platelets); plasma itself is roughly 90-92% water.
• Plasma minus clotting factors (chiefly fibrinogen) is serum — a distinction examiners like to test.
• Plasma proteins: albumin maintains osmotic pressure, globulins provide immunity, and fibrinogen enables clotting.