What Is Blood Made Of?

Blood is made of blood cells floating in plasma. The plasma is mostly made of water with chemicals in it. These chemicals include proteins, hormones, minerals, and vitamins.

What are the 3 Basic Types of Blood Cells?

  1. Red blood cells (RBCs) are also called erythrocytes. They make up almost half of blood. Red blood cells are filled with hemoglobin. That's a protein that picks up oxygen in the lungs and brings it to cells all around the body.
  2. White blood cells (WBCs) are also called leukocytes. They fight disease and infection by attacking and killing germs that get into the body. There are several kinds of white blood cells, each of which fights a different kind of germ.
  3. Platelets are also called thrombocytes. They are small pieces of cells that help blood clot and stop bleeding.

How are Blood Cells Formed?

The process of making blood cells is called hematopoiesis. Blood cells are made in the bone marrow. That's a spongy tissue located inside some bones. It contains young parent cells called stem cells. These blood-forming stem cells can grow into all 3 types of blood cells. They make copies of themselves, and they also produce mature blood cells. When blood cells are fully mature and functional, they leave the bone marrow and enter the blood. Healthy people have enough stem cells to keep making all the blood cells they need every day.

When the bone marrow fails to keep up with the body's needs and doesn't produce enough red cells, white cells or platelets or when those blood cells that are produced are damaged or defective, you have bone marrow failureAplastic anemia, MDS and PNH are bone marrow failure diseases.

What is Bone Marrow Failure?

When the bone marrow fails to keep up with the body's needs and doesn't produce enough red cells, white cells or platelets, or when those blood cells that are produced are damaged or defective, you have bone marrow failure.  Aplastic anemia, myelodysplastic syndromes and paroxysmal nocturnal hemoglobinuria are bone marrow failure diseases.