Tutoring biology, you might be asked about blood plasma. The tutor mentions its defintion.
the liquid that holds the red blood cells, white blood cells, and platelets. The plasma consists of water and substances suspended or dissolved therein: proteins, salts, etc.
Plasma does not include blood cells or platelets.
Mader, Sylvia S. Inquiry into Life, 9th ed. Toronto: McGraw-Hill, 2000.
Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.