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Blood. Blood. Blood is a Connective Tissue. The Cells of Blood are Called “Formed Elements”. Agranulocytes Monocytes Cells divide and differentiate Lymphocytes . Granulocytes Neutrophils
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Blood Blood is a Connective Tissue
The Cells of Blood are Called “Formed Elements” Agranulocytes Monocytes Cells divide and differentiate Lymphocytes . Granulocytes Neutrophils Acidophils Terminally differentiated Basophils . Erythrocytes No organelles . Platelets Cell fragments .
The Hematocrit. Left: Tubes with blood before centrifugation. Right: After centrifugation. The erythrocytes represent 43% of the blood volume in the centrifuged tube. Between the sedimented erythrocytes and the supernatant light-colored plasma is a thin layer of leukocytes called the buffy coat.
Erythrocytes 99.5% of the formed elements of blood. Biconcave disks 7.5u in diameter. Lack cell nucleus, other organelles, RNA . Have a specialized cell membrane Have enzymes to produce ATP and NADPH Circulate for 120 days.
The Leukocytes or white blood cells Granulocytes Neutrophils Acidophils Basophils Agranulocytes Monocytes Lymphocytes
Neutrophils 60% of leukocytes Multilobed nucleus Very small specific granules Phagocyte for bacteria
3 Days 4 Days 4 Days 6-7 Hours 1-4 Days CONNECTIVE TISSUE
Acidophil = Eosinophil ~5% of Leukocytes Bi-lobed nucleus Large granules (~1um) Functions in allergies and worm infections
Basophils < 1% of leukocytes Elongated S-shaped nuclei Large heterogeneous, basophilic granules Secrete histamine and heparin
Monocytes 5% of leukocytes Pale irregular nucleus Largest of the leukocytes Precursors to macrophages Not phagocytic in blood
Main Functions of Macrophages • Ingest bacteria and cellular debris • Secrete various chemical messengers • Coordinate cell activities in • inflammation and wound healing • Remove aged red blood cells • 5. Roles in antibody formation
The Mononuclear Phagocyte SystemMPS Includes monocytes and all cells that come from them. Examples: histiocytes of C.T. Kupffer cells of liver microglia of brain alveolar macrophages Excludes unrelated phagocytic cells that do not come from monocytes. Examples: neutrophils, Sertoli cells, mesangeal cells
Tweedledee told Alice in Alice in through the looking glass Contrariwise if it was so it might be and if it were so it would be. But as it isn’t it ain’t. That’s logic. ….and that’s the reticuloendothelial system.
Lymphocytes Small Medium Large constitute about 30% of leukocytes. have a small dense round nucleus and a small rim of cytoplasm. can divide and differentiate.
Cytological Structures in Platelets Structural components microtubules, actin, myosin Granules alpha, delta, lambda Membranes systems plasmalema, open canalicular system, dense tubular system
Functions of Platelets Primary aggregation Secondary aggregation Blood coagulation Clot retraction Clot removal