13 May 2019 Blood cells consist of: Red blood cells White blood cells Platelets. Red blood cells, or erythrocytes, are the cells responsible for transporting oxygen and for the red colour of blood. They contain haemoglobin, which is a protein that binds to oxygen so it can be carried in the blood. White blood cells, or leukocytes , are the cells essential for fighting infection and other attacks on the body, and make up part of the immune system. There are five types of leukocyte, which can be grouped as follows: Granulocytes (neutrophils, eosinophils and basophils) Agranulocytes (lymphocytes and monocytes) Platelets or thrombocytes are the smallest blood cells and play a key role in coagulation. They help control bleeding. Where blood cells are produced Blood cells are produced in the bone marrow , a spongy substance in the internal cavities of the bones. For blood cells to be produced correctly, it is necessary: For the bone marrow to be healthy; For it to receive the necessary nutrients carried by the blood. All blood cells originate from stem cells. There there are two types in the bone marrow: Lymphoid; Myeloid. After they are formed, the bone marrow releases the blood cells into the bloodstream. Millions of blood cells are produced every day. Each type has an average life span ranging from a few hours to over 100 days. As the number of cells of each type remains relatively constant under normal conditions, millions of blood cells also die every day. This article was written with the support of physicians and other clinical professionals from the Hospital da Luz network. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
