The fluid part of blood (mainly water) that surrounds blood cells and transports them is known as:

• A. Platelets
• B. Plasma
• C. Red Blood Cells
• D. White Blood Cells

Answer: (B)

The fluid part of blood that surrounds the cells and transports them is plasma. It is mostly water and dissolved substances, forming the medium in which red blood cells, white blood cells, and platelets float as blood flows. Plasma carries oxygen, carbon dioxide, nutrients, hormones, and waste products, and it contains proteins that help regulate blood volume and clotting. The other options are specific blood cells or fragments: platelets are involved in clotting, red blood cells carry oxygen, and white blood cells defend against infection. Plasma is the correct answer because it is the liquid matrix in which all the blood cells are suspended and transported.