Transcript blood
Cells and membrane bound components of blood: Why are they there? Erythrocytes – for hb Leukocytes – in transit to CT. Granulocytes - neutrophils phagocytose bacteria - eosinophils phag. Ab/ag and paras. - basophils signal to stimul. Leukocy. and release vasodil. - monocytesmacrophages, phag. Agranulocytes – lymphocytes, immune fn for recogn invasion Platelets - aggregation 1 Blood: - blood smear air dry dyes to show specific Characteristics of the cells, Wright stain or Giemsa Stain The colors in a blood smear: - methylene blue gives blue color to acidic components - eosin gives pink to alkaline components -oxidized methylene blue called azures color components Reddish blue 2 In the blood: Erythrocytes – biconcave shaped disc. - 7.5 microns wide -2 microns to 1 micron thick -This shape gives a large surface area for gas exchange. -Precursor in bone marrow contain nucleus -No organelles -Life span of erythrocyte is 120 days. -Lots of hb, can’t see 3 Leukocytes, white blood cells: -much fewer than rbc -Don’t function in the blood, -move by diapedesis to function in CT Granulocytes - neutrophils, eosinophils, basophils Agranulocytes 4 Neutrophils: -most common wbc. -Phagocytic -Destroy bacteria in CT spaces -9 to 12 micron diameter -Multilobed nucleus, lobes connected by chromatin threads -Why the granules? 3 kinds, specific, azurophilic, tertiary -Specific granules contain enz for antimicrobial function -Azurophilic granules are lysosomes with enz. -Tertiary granules gelatinase, cathepsins, mb glycoproteins 5 Neutrophil granules and neutrophil function: -use granules to phagocytose and destroy bacteria Neutrophils role along endothelial walls by binding selectin Onto selectin receptors on endothelial cells in postcapillary Venules. Chemotactic agents bind onto neutrophil plasmalemma Tertiary granules release stuff to ecm Gelatinase chops up basal lamina Neutrophil migration facilitated Glycoproteins into mb 6 Contents of specific granules: -aid in neutrophil migration and attack micro-organisms -Phagocytosis enz an stuff in azurophilic granules Do their thing to destroy the microbes Neutrophils have reactive oxygen compounds, superoxides For microbe destruction. Pus is dead neutrophils 7 Eosoinophils phagocytose antigen/ab complexes, kill parasites -few of the wbc’s are eosinophils -Round in the blood -Sausage shaped bilobed nucleus with 2 lobes connected -Eosinophil granules: specific granules and azurophilic granules Specific granules: stain deep pink -agents in combating parasites and enzymes -Azurophilic granules: lysozomes similar to neutrophil ones Degrade parasitic worms and AB/AG reactions 8 Basophils -rarest of wbc’s Round, becoming pleomorphic during migration 8 to 10 microns S-shaped nucleus blocked by granules Granules? Specific and azurophilic -specific, very dark staining with histamine, heparin etc. -Azurophilic granules, lysosomes 9 Basophil function: -antigens present plasma cells make IgE Ige’s attach to basophil receptors The next time that the antigens enter the body The antigens bind to basophil (mast cell) IgE’s Contents of specific granules released. Including histamine, arachadonic acids, leukotrienes vasodilation and leukotriene induced leukocyte Activation so they migrate to the site of antigenic challenge 10 Monocytes: largest of circulating blood cells. -become known as macrophages when they enter CT spaces -12 to 15 microns -large, acentric kidney shaped nucleus -bluish gray cytoplasm -Azurophilic granules -Macrophages are avid phagocytes 11 Agranulocytes: lymphocytes -are a little larger than erythrocytes, 8 to 10 microns. -Slightly indented round nucleus occupies most of the cell. -S, M, L. -S – 8 to 10 microns -M – 12 to 15 -L – 15 to 18 microns -No function in the blood 12 Platelets -2 to 4 microns Derive from megakaryocytes in the bone. Become activated if the endothelial cell is damaged. When the platelet adheres to the endothelium, and get platelet aggregation 13