blood

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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.
- monocytesmacrophages, phag.
Agranulocytes – lymphocytes, immune fn for recogn
invasion
Platelets - aggregation
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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