Formed+Elements

Three main types of formed elements of blood and their several subtypes:
1. **Red Blood Cells (RBC) - erythrocytes** - Have several functions, the most important is to help transport carbon dioxide (CO2). Carbon dioxide is a waste product produced by the energy-producing processes of all living cells, and can be harmful. The red blood cell is "caved in" on both sides so that the center is thin and the edges are thicker. Has a red pigment (hemoglobin) which unites with oxgen to for oxyhemoglobin. Oxyhemoglobin makes it possible to transport large quanities of oxygen to body cells. Hemoglobin can also help carry CO2, only in small portions, which then forms carbaminohemoglobin. 2. **White Blood Cells (WBC)- leukocytes**- Have a function that is vital, they defend the body from cancer cells that form inside our tissues and from microorganisms that have succeeded in invading our body. WBC's are broken down into two different types: a. __Granular Leukocytes__: (having granules in their cytoplasm) (1) //Neutrophils//- Most numerous, called phagocytes, protect the body from invading microorganisms by taking them into their own cell bodies and digesting them by the process of phagocytosis. (2) //Eosinophils//- weak phagocytes. Most important function is to protect against infections caused by parasitic worms. (3) //Basophils//- found in peripheral blood, they secrete a horomone called histamine, which is released during and inflammatory reaction. They also produce heparin, which is a potent anticogulant. Heparin helps prevent blood from clottinng as it flows through the blood vessels of the body. b. __Nongranular leukocytes__ (do not have granules in their cytoplasm) (1) //Lymphocytes-// Help protect us against infections. Function in the immune mechanism, the complex process that makes us immune to infectious diseases. B Lymphocytes secrete specialized proteins, called antibodies, which specifically act to destroy particular bacteria, viruses, or chemical toxins. T. Lymphocytes protect us by directly attacking virally infected or cancerous cells. The lymphocytes are formed by lymphatic tissue, which is primarly located in the lymph nodes, thymus, and spleen. (2) //Monocytes//- are the largest leukocytes. They are aggressive phagocyes, they are capable of engulfing larger bacterial organisms and cancer cells. Macrophages are specialized monocytes that grow several times their original size after migrating out of the blood stream. 3. **Platelets- thrombocytes**- essential part of blood clotting, or coagulation.