blood summary

Study the compositions, functions, and disorders of blood

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Below is the article summary. For the full article, see blood.

blood, Circulatory fluid (see circulation) in multicellular animals. In many species it also carries hormones and disease-fighting substances. Blood picks up oxygen from the lungs and nutrients from the gastrointestinal tract and carries them to cells throughout the body for metabolism. It picks up carbon dioxide and other wastes from those cells and transports them to the lungs and excretory organs. Blood composition varies among species. Mammalian blood consists of plasma, red and white cells (erythrocytes and leukocytes), and platelets (thrombocytes). Blood disorders include polycythemia (abnormal increase in the number of circulating red blood cells), anemia, leukemia, and hemophilia. See also ABO blood-group system; blood analysis; blood bank; blood pressure; blood transfusion; blood typing; Rh blood-group system.

lymphocyte Summary

Lymphocyte, type of white blood cell (leukocyte) that is of fundamental importance in the immune system because lymphocytes are the cells that determine the specificity of the immune response to infectious microorganisms and other foreign substances. In human adults lymphocytes make up roughly 20

white blood cell Summary

White blood cell, a cellular component of the blood that lacks hemoglobin, has a nucleus, is capable of motility, and defends the body against infection and disease by ingesting foreign materials and cellular debris, by destroying infectious agents and cancer cells, or by producing antibodies. In

Marcello Malpighi Summary

Marcello Malpighi was an Italian physician and biologist who, in developing experimental methods to study living things, founded the science of microscopic anatomy. After Malpighi’s researches, microscopic anatomy became a prerequisite for advances in the fields of physiology, embryology, and

Claude Bernard, detail of a lithograph by A. Laemlein, 1858

Claude Bernard Summary

Claude Bernard French physiologist known chiefly for his discoveries concerning the role of the pancreas in digestion, the glycogenic function of the liver, and the regulation of the blood supply by the vasomotor nerves. On a broader stage, Bernard played a role in establishing the principles of