What is the liquid portion of blood called?

What is the liquid portion of blood called?

• A. Plasma
• B. Red blood cells
• C. Serum
• D. Platelets

Answer: (A)

Plasma is the liquid portion of blood. It’s the pale, straw-colored fluid that makes up about half of blood and contains water, dissolved proteins (like albumin and the clotting factors), electrolytes, nutrients, hormones, and wastes. When blood is separated without clotting, the liquid above the cells is plasma. If blood is allowed to clot and the liquid is drawn afterward, that liquid is serum, which lacks fibrinogen and other clotting factors. The other options—red blood cells and platelets—are cellular components, not the liquid portion.

Plasma is the liquid portion of blood. It’s the pale, straw-colored fluid that makes up about half of blood and contains water, dissolved proteins (like albumin and the clotting factors), electrolytes, nutrients, hormones, and wastes. When blood is separated without clotting, the liquid above the cells is plasma. If blood is allowed to clot and the liquid is drawn afterward, that liquid is serum, which lacks fibrinogen and other clotting factors. The other options—red blood cells and platelets—are cellular components, not the liquid portion.