Transcript Hematology

Hematology
I. CVS= heart +
blood +
vessels
(integrated with
immune
system)
both =
circulatory
system
II. Functions of blood;
1. transport gases, nutrients,
hormones, metab. wastes
2. reg. pH + ion conc. of interstitial
fluid (electrolytes)
3. restricts fluid loss at injury
4. defends against toxins and
pathogens
5. stabilizes body temp.
III. Characteristics of blood
• temp= 100 degrees F
• pH= 7.35-7.45 (narrow
range)
• viscosity= 5 times more
than water
• amount= 7% of body weight
in kg
IV. Composition; fluid CT
• fluid is called plasma
• cells (formed elements) are;
– RBC- erythrocytes
– WBC- leukocytes
– Platelets – cell fragments
• Hematocrit- shows % of solid elements
• Centrifuged tube shows parts
• (refer to plate)
V. Plasma characteristics;
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straw colored
46-63% of whole blood
92% water
contains electrolytes and metabolites
contains 3 types of proteins
1. albumins- 60% of proteins; combines w/ and
transports fatty acids and hormones,
contributes to osmotic pressure
2. globulins- 35%; ex.
Immunoglobulins(antibodies), transport
globulins
3. fibrinogen- 4%; involved in clotting, blood
w/o it is called serum
VI. Erythrocytes;
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- made in red bone marrow
-1/3 of all cells in body
very specialized
shape is biconcave disc (p. 629)
1. increases SA:V
2. stackable to form rouleaux
3. flexible due to spectrin
enucleated, no mitosis
no mitochondria or ribosomes
don’t use O2 (use anaerobic resp.)
packed with hemoglobin (Hb)
Life span 120 days
VII. Hemoglobin (p. 630)
• 4 aa chains –2 alpha + 2 beta
• each chain wraps around a
heme pigment
• heme will chem. comb. w/
oxygen
• Hb + O2
HbO2
• Oxyhemoglobin makes bl.
bright red
• O2 can disassociate making
deoxyhemoglobin and bl.
becomes burgundy
VIII. Recyclying RBCs –p. 632
1. RBCs become become engulfed by phagocytes of
liver, spleen and bone marrow.
- alpha and beta chains broken down into amino
acids and metabolized or released into bl.
-heme stripped of its iron and becomes biliverdin
(green)
2 . biliverdin becomes bilirubin (yellow)
3. Bilirubin transported to liver to be excreted in bile.
-.Jaundice develops when bile can’t be secreted.
2. Fe carried via transferrin to marrow to be recycled
3. . Excess Fe stored in ferritin in liver
IX. Hematopoiesis- production of
cells
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• refer to p. 643
• erythropoiesis- RBC formation
X. WBC’s
• – most work outside the bl. stream inside tissues
or in lymph organs
• -2 groups- see plate
A. Granular- (-phil)
neutrophil- 50-70%
eosinophil- 2-4% (stain red)
basophil- <1% (stain blue)
B. Agranular- (-cyte)
lymphocyte- 20-30%
monocyte- 2-8%
XI. WBC characteristics;
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Ameboid movement
Diapedesis
Chemotaxis
Phagocytosis
Functions of WBC’ (refer to chart p.
642)
Monocytes
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largest WBC
spherical
tissue macrophage
largest component of pus
Neutrophils
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lobed nucleus,polymorphs
pale colored granules
very mobile, fast
first to injury site
10 hour life span
“eat” bacteria – form pus
die and release chemicals to
attract more cells
Eosinophils
• “eat” cells marked with
antibodies
• granules contain histamine
• respond in allergic reactions
• defend against parasitic
infestations
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(ex. hookworm and
tapeworm)
Basophils
• granules filled with heparin and histamine
• respond in inflammation
Lymphocyte
• large nucleus with little halo of cytoplasm
• immune response
• types of lymphocytes
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(most not in bl.v.)
– T cells- attack foreign cells
– B cells- produce antibodies
– NK cells- destroy abnormal cells
• http://en.wikipedia.org/wiki/White_blood_c
ell
XII. Platelets- thrombocytes
• (not complete cells) p. 643
• -produced by megakaryocyte in bone
marrow
• -responsible for hemostasis (clotting
XIII. Hemostasis- p. 647
1. Vascular phase – immediate contraction of bl.v
2. Platelet phase 0-30 secs
a. damaged cells release chemicals
b. damaged cells become sticky and contract
c. platelets arrive at wound site and stick to damaged areas
forming a “plug”
3. Coagulation phase 30 secs-8 min
a. coagulation begins involving blood proteins called
clotting factors (30 sec after
(work in a chain reaction and need Ca+
and K+ to work) refer to p. 648
b. prothrombin forms thrombin enables fibrinogen to form
fibrin
c. prostaglandins released form tissues attract more
platelets and clot forms
(aspirin inhibits prostaglandin production)
d. clot dries on surface and forms scab which pulls
wounded tissue together
hemolytic anemia in the newborn
• Occurs when a fetus is Rh+ and mother is Rh−
• the mother will produce antibodies against the fetal
antigen when blood is exchanged during birth.
• complicates future pregnancies, because her antibodies
will enter the fetal circulation system and react with fetal
blood, causing hemolysis.
• Treatment= Anti-Rh+ antibody is injected into the mother
after her first delivery.
-destroys the fetal Rh+ cells in the mother's
circulation preventing Rh +antibody production in the
mother
-next child will not be at risk for hemolytic anemia.