Download Composition of Blood

Erythrocytes
 Most abundant cell in the body
 Number of circulating RBCs in peripheral venous
blood
 Derived from erthroblasts
 Survive 120 days/Bioconcave
 RBC values vary according to gender and age
 Women lower, tend to decrease with age
 Decreased by more than 10% = anemia
 Primary function: tissue oxygenation
Erythrocyte indices
 Mean corpuscular volume (MCV)
 Mean corpuscular hemoglobin (MCH)
 Mean corpuscular hemoglobin concentration (MCHC)
MCV
 Mean volume of all the erythrocytes counted in the
sample
 MCV low = microcytic
 Norm MCV = normocytic
 MCV high = macrocytic
Normocytic
 Iron deficiency (detected early)
 Chronic illness
 Acute blood loss
 Aplastic anemia
 Acquired hemolytic anemia
 (from a prosthetic cardiac valve)
Microcytic
 Iron deficiency (detected late)
 Thalassemia
 Lead poisoning
Macrocytic
 Vitamin B 12 or folic acid deficiency
 Chemotherapy
 Myeloid leukemia
 Ethanol toxicity
 Thyroid dysfunction
MCH
 Measure of the average amount of weight of
hemoglobin within an RBC
 Macrocytic anemias: the MCHC is increased if the size
of the RBC is large
 Microcytic anemia, hypochromic anemia: the MCH is
decreased if the size of the RBC is small of the
hemoglobin is diminished
MCHC
 Mean concentration of hemoglobin in the red cell.
Since whole blood is about one-half cells by volume,
and all the hemoglobin is confined to the cells, you
would correctly expect the MCHC to be roughly twice
the value of hemoglobin in whole blood
White Blood Cells
(Leukocytes)
 Granulocytes
 Neutrophil
 Eosinophil
 Basophil
 Mast cells
 Agranulocytes
 Monocyte
 Lymphocyte
Neutrophil
 Circulate for about 8 hours before proceeding to the
tissues, where they live for about a week
 Most numerous, 55%
 Produced as a response to acute body stress
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Infection
Infarction
Trauma
Emotional distress
 Phagocytosis invaders
 Foreign cells
 Toxins
 Viruses
Neutrophils..
 Found near sites of infection or injury where they will
stick to the walls of the blood vessels and engulf any
foreign particles that try to enter the bloodstream
 Found in the pus of wounds
 Band neutrophils
 Indicator of acute stress
 Segmented neutrophils
 Most mature type
Eosinophil
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Derived from different stem cells
Hallmark = presence of bright orange large granules
Ameboid movement = phagocytosis
Seen at sites:
 Invasive parasitic infestations
 Allergic (immediate hypersensitivity) response (IgE)
 Critical function:
 Inactive slow reacting substance of anaphylaxis
 Neutralize histamine
 Inhibit mast cell degranulation
Mast Cells
 Central cell in inflammation
 Found in vascularized connective tissue
Basophils
 Large deep purple granules
 Precise function not understood
 Contain histamines (causes vasodilation)
 Heparin (anticoagulant)
 High number of these cells:
 Hemolytic anemia
 Chicken pox
Lymphocytes
 In the immune/inflammatory response:
 Neutrophils and monocytes are the brutes
 Major cells of immune system
 Lymphocytes are the brains

“bubble-boy”
 T-lymphocytes:
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Act against virus infected cells and tumor cells
AIDS keep a careful watch on their T-cell level, an indicator of
the AIDs virus’ activity
 B-lymphocytes:

Produce antibodies
Natural Killer
 Natural killer (NK) cells
 Kill tumor cells and virally infected cells
 Procedure cytokines involved in immune responses
Monocyte
 Largest of the leukocytes
 Phagocytic and defend the body against viruses and
bacteria
 Elevated cell count:
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Malaria
Endocarditis
Typhoid fever
Rocky Mountain spotted fever
Thrombocytes
 Platelets
 Disk-shaped cytoplasmic fragments
 Formed by fragmentation of megakaryocytes
 Secrete a hormone called serotonin which constricts
torn blood vessels
 Essential for blood coagulation and control of
bleeding
 Live 10 days and then removed by spleen