Blood circulates throughout the body, transporting substances essential to life. Here, learn about the components of blood and how it supports human health. Blood Basics Blood is a specialized body fluid. It has four main components: plasma, red blood cells, white blood cells, and platelets. The blood that runs through the veins, arteries, and capillaries is known as whole blood—a mixture of about 55% plasma and 45% blood cells. About 7% to 8% of your total body weight is blood. An average-sized man has about 12 pints of blood in his body, and. Detailed information on blood, including components of blood, functions of blood cells and common blood tests. Blood is a liquid connective tissue made up of blood cells and plasma that circulate inside the blood vessels under the pumping action of the heart. Blood is a fluid that transports oxygen and nutrients to cells and carries away carbon dioxide and other waste products. It contains specialized cells that serve particular functions. These cells are suspended in a liquid matrix known as plasma. Blood is a specialized form of connective tissue and body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells of the body, and transports metabolic waste products away from those same cells. [1] Blood is composed of blood cells suspended in plasma. Plasma, which constitutes 55% of blood fluid, is mostly. Blood plasma is the yellow liquid in which blood cells float. Plasma is made up of nutrients, electrolytes (salts), gases, non-protein hormones, waste, lipids, and proteins. These proteins are albumin, antibodies (also called immunoglobulins), clotting factors, and protein hormones. Plasma that does not have the protein fibrinogen is called serum and cannot clot. Adults have about 3 liters of. Blood Basics Blood is a specialized body fluid. It has four main components: plasma, red blood cells, white blood cells, and platelets. The blood that runs through the veins, arteries, and capillaries is known as whole blood—a mixture of about 55% plasma and 45% blood cells. About 7% to 8% of your total body weight is blood. Blood is a specialized fluid that constantly flows throughout your body. It’s made of plasma, red blood cells, white blood cells and platelets. Blood, the journal of the American Society of Hematology, publishes cutting-edge research and clinical advances in hematology and oncology.