Whole blood makes up about 7% of a person's body weight and consists primarily of red blood cells, white blood cells, platelets and plasma. The average human adult has about 1 ‐ 1½ gallons of blood traveling through their circulatory system.
White blood cells fight infection and help you develop immunity to disease. They make up less than 1% of your blood.
Plasma is the pale-yellow liquid part of your blood that holds all of the blood cells. It makes up about 55% of your total blood.
Plasma transports water, nutrients, minerals, medications, and hormones throughout your body. It also carries waste products to your kidneys. Your kidneys then filter out the waste from your blood. Plasma made up of water, protein, lipids (fats), and hormones.
Red blood cells (erythrocytes). These carry oxygen from the lungs to the rest of the body.
Blood cells are made in the bone marrow. The bone marrow is the soft, spongy material in the center of the bones that produces about 95% of the body's blood cells.
White blood cells help heal wounds not only by fighting infection, but also by taking in matter, such as dead cells, tissue debris, and old red blood cells.
Blood plasma can be separated from the cells by spinning blood in a device known as a centrifuge until the cells collect at the bottom of the tube.
As well as delivering important substances to our cells, blood also helps take away unwanted waste products.
There are other organs and systems in our bodies that help regulate blood cells. The lymph nodes, spleen, and liver help regulate the production, destruction, and differentiation (developing a specific function) of cells. The production and development of new cells is a process called hematopoiesis.