Chapter 18 Blood Composition
What are the three functions of blood?
Transportation, Regulation, and Protection
What makes up the formed elements of the blood?
Red Blood Cells
White Blood Cells-
-Granular leukocytes, neutrophils, eosinophils, basophils.
-Agranular leukocytes, T and B lymphocytes and natural killer cells, monocytes. What is the percentage of total blood volume occupied by RBCs? Hematocrit
What is the normal range of hematocrit for adult females? Adult males? women:38-46%
What does a significant drop in hematocrit indicate?
Anemia, a lower than normal number RBC's
What does an abnormally high percentage of RBC's indicate?
What are causes of polycythemia?
abnormal RBC production, tissue hypoxia, dehydration, and blood doping or the use of EPO by athletes. What is hemopoiesis?
The process by which the formed elements of blood develop.
What is the primary site of hemopoiesis?
Red bone marrow.
What is thrombopoietin?
TPO, is a hormone produced by the liver that stimulates the formation of platelets from megakaryocytes. What does Erythropoietin?
EPO, increases the number of red blood cell precursors.
What are erythrocytes?
red blood cells
What is the oxygen carrying protein?
In addition to oxygen, hemoglobin also carries carbon dioxide. What percentage of the total carbon dioxide is carried by hemoglobin and what happens to the remaining carbon dioxide? 23% of the carbon dioxide is carried by hemoglobin and the remaining is dissolved in plasma or carried as bicarbonate ions. Besides transporting oxygen and carbon dioxide, what else does hemoglobin play a role in? regulation of blood flow and blood pressure.
How long do RBC's live and why?
about 120 days because of the wear and tear their plasma membranes undergo as they squeeze through blood capillaries. What is erythropoiesis?
The production of RBC's
What is hypoxia?
cellular oxygen deficiency
What are leukocytes?
white blood cells
Which WBC's are included under granular leukocytes, agranular leukocytes? Granular - neutrophils, eosinophils, and basophils.
Agranular - lymphocytes and monocytes.
What is leukocytosis?
an increase in the number of WBC's.
What is leukopenia?
An abnormally low level of white blood cells.
What can cause leukopenia?
radiation, shock, and certain chemoterapeutic agents.
Once pathogens enter the body, the general function of white blood cells is to combat them by what? phagocytosis or immune responses.
Which WBC responds most quickly to tissue destruction by bacteria? neutrophils.
What does a high eosinophil count ofter indicate?
allergic condition or a parasitic infection.
At sites of inflammation, basophils leave capillaries, enter tissues, and release granules that contain heparin, histamine, and serotonin. What do these substances do? they intensify the inflammatory reaction and are involved in hypersensitivity reactions. What are three main types of lymphocytes?
B-cells, T-cells, and Natural Killer (NK) Cells
What are B-cells effective in?
destroying bacteria and inactivating their toxins.
What do T-cells do?
attack viruses, fungi, transplanted, cancer cells, and some bacteria, and are responsible for transfusion reactions, allergies, and the rejection of transplanted organs. Platelets help stop blood loss from damaged blood vessels by forming a what? platelet plug
Phagocytosis. Destruction of bacteria with lysozyme, defensins, and strong oxidants. Neutrophils
Combat effects of histamine in allergic reactions, phagocytize antigen-antibody complexes, and destroy certain parasitic worms. Eosinophils.
Liberate heparin, histamine, and serotonin in allergic reactions that intensify overall inflammatory response. Basophil
Mediate immune responses, including antigen0antibody reactions. B cells develop into plasma cells, which secrete antibodies, T cells attack invading viruses,...
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