Chapter 11 Blood AnalysisVocabulary

  1. Hemoglobin – the oxygen carrier that gives red blood cells their color. It is composed of four globin (protein) chains, each with a heme group.
  2. False positive – a test result that comes out positive when it is not.
  3. Chemiluminescence – the emission of light from a chemical reaction. Within an organism such as a firefly, it is called bioluminescence.
  4. Precipitin Test – test that distinguishes between human and animal blood
  5. Serum – a liquid that separates from clotted blood
  6. Antigen – foreign substance or cell in the body that is capable of causing disease or reacts with antibodies. The presence of antigens triggers an immune response, usually antibody production.
  7. Agglutinate – an allergic reaction, generally antigen-antibody, where red blood cells clump together, usually in response to a particular antibody.
  8. Antiserum – human or animal serum containing antibodies that are specific for one or more antigens.
  9. Serology – the laboratory study of body fluids using specific antigen and serum antibody reactions.
  10. Plasma – the fluid portion of blood, obtained by centrifuging a sample of whole blood.
  11. Platelets – cell fragments that help form blood clots at wound sites. Also called thrombocytes.
  12. Erythrocytes – red blood cells – donut-shaped cells that carry oxygen throughout the body.
  13. Leukocytes – white blood cells – cells that police the body by destroying foreign materials.
  14. ABO – a basic classification system for blood types based upon the reaction of antigens and antibodies.
  15. Rh factor – a basic blood factor, independent of ABO types.Mothers must be concerned about the Rh factor during pregnancies for second and subsequent children, because agglutination can occur in an Rh+ embryo. This is called erythroblastosis fetalis and can kill the fetus.
  16. Blood factors – a specific combination of antigens, enzymes, and proteins in the blood.
  17. Secretors – people whose blood type antigens are also found in other body fluids.
  18. Antibodies – proteins secreted by white blood cells and attach to specific antigens. In the blood or secretory fluids, antibodies tag, destroy, or neutralize bacteria, viruses, or other harmful toxins, producing an immune response. When a rabbit is injected with human blood, antibodies are produced to fight the foreign invader. The rabbit serum containing these antibodies is used in the precipitin test. The “fight” results in agglutination, much like a chemical precipitation.
  19. Cell-surface protein – proteins embedded in the cell membrane.
  20. Allele – one member of a pair of genes occupying a specific spot on a chromosome that controls the same trait. For example, a pair of alleles may control the same trait such as eye color.
  21. Metabolites – organic molecules involved in the process of metabolism, which is defined as the sum of all chemical processes occurring in an organism.
  22. Lines of convergence – a two-dimensional view of the intersection of lines formed by drawing a line through the main axis of at least two drops of blood that indicates the general area of the source of the blood spatter.
  23. Point of origin – a three-dimensional view formed using lines of convergence and angles of impact of at least two different drops of blood to identify the source of location of blood spatter.
  24. Satellite drop of blood – secondary drop formed when some blood breaks free from the main contact drop of blood.

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