Blood Glossary


A – N of Blood



Alveoli - Air sac of the lungs, formed by the terminal dilation of tiny air passageways.


Antibody - A protein that is made by certain white blood cells (lymphocytes), in the body, in response to the invasion of a foreign substance.


Antigen - A substance that when introduced into the body stimulates an immune response.


Aorta - The main trunk of the arterial system, carrying blood from the left ventricle of the heart to all of the body except the lungs.


Arteries - Blood vessels that carry blood from the heart to any part of the body. The exception to this rule is the Pulmonary artery.


Bacteria - One-celled organisms, spherical, spiral, or rod-shaped and appearing singly, in chains, or in clusters.


Blood - The fluid that circulates in the principal vascular system of human being and other vertebrates: in humans consisting of plasma in which the red blood cells, white blood cells,and platelets are suspended.


Bronchi - The main branches of the trachea.


Capillaries - The tiny blood vessels between the terminations of the arteries and the beginnings of the veins.


Chemotaxis - Movement of a cell toward of away from a chemical stimulus.


Cytoplasm - A jellylike material that surrounds the nucleus of a cell and contains most of the cell's organelles.


Differentiation - (of cells or tissues) to change from relatively generalized to specialized kinds, during development.


Erythrocyte - A red blood cell.


Fibrin - The insoluble protein end product of blood coagulation.


Germs - Any micro-organisms that cause disease.


Granulocyte - A circulating white blood cell having prominent granules in the cytoplasm and a nucleus of two or more lobes.


Hemoglobin - The oxygen-carrying protein of red blood cells that gives them their red color and serves to carry oxygen to the tissues.


Immunity - The condition that permits either natural or acquired resistance to disease. 


Leukocyte - A white blood cell.


Lymphocyte - A type of white blood cell having a spherical nucleus surrounded by a thin layer of nongranular cytoplasm.


B Lymphocyte - A lymphocyte that is involved in the production of antibodies.


T Lymphocyte - A lymphocyte that helps in the priming of B lymphocytes to make antibody or is directly involved in attacking foreign cells, such as tumor cells.


Marrow - A soft, fatty, vascular tissue in the interior cavities of bones that is a major site of blood cell production.


Megakaryocyte - A large bone marrow cell having a lobulated nucleus (one with lobes); the source of blood platelets.


Mitosis - The usual method of cell division.


Monocyte - A large, circulating white blood cell, formed in bone marrow and in the spleen. When in the tissue a monocyte becomes a macrophage.


Macrophage – Is the same as a monocyte except it remains in the tissue. It ingests large foreign particles and debris.


Nucleus - The part of the cell that holds genetic information such as DNA. 


Nutrients - Substances that give sustenance to an organism.