Term
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Definition
1. macrophages in spleen, liver, or red bone marrow phagocytize worn RBCs
2. globin and heme split
3. globin broken down into aa- used to synthesize other proteins
4. Iron (Fe3+) removed from heme and associates with transferrin
5. in spleen and liver cells, Fe3+ detaches from transferrin and bind to iron-storage protein, ferritin
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Term
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Definition
6. upon release, it reattaches to transferrin
7. carried to red bone marrow, where RBC precursor cells endocytose it and use it for Hg synthesis (iron needed for 8. heme portion)
8. erythropoiesis in red bone marrow result in RBC production
9. when iron removed from heme, the non-iron portion is converted to biliverdin (green), and then bilirubin (yellow)
10. bilirubin enters blood and is transported to the liver |
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Term
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Definition
11. within the liver, bilirubin is released into bile, which passes into the small intestine, then the large intestine
12. in the large intestine, bacteria convert bilirubin into urobilinogen
13. some urobilinogen is reabsorbed by blood, converted to a yellow pigment, urobilin and excreted in urine
14. most urobilinogen is eliminated in feces in the form of stercobilin (brown pigment)
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Term
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Definition
| free iron ions bind to and damage cells, so transferrin and ferritin act as protective “protein escorts” and as a result only small amounts of iron are available inside cells for synthesis |
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Term
| Common Conseq. Of Iron Overload |
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Definition
in cases of iron overload, the amount of iron in the body builds up
we have no method for eliminating excess iron
common consequences include diseases of the liver, heart, pancreas and gonads |
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Term
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Definition
Production of RBCs.
occurs in the red bone marrow with precursors called proerythroblast.
Proerythroblasts divide repeatedly producing cells that start synthesizing Hg.
Ultimately, a cell ejects its nucleus (causing the characteristic shape) and becomes a reticulocyte, which maintains some mitochondria, ribosomes, and ER |
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Term
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Definition
bloodcell which maintains some mitochondria, ribosomes, and ER.
Reticulocytes escape from bone marrow into the blood
In 1-2 days, they mature into RBCs and eject their remaining organelles |
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Term
| If erythropoiesis does not keep up with destruction . . . |
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Definition
| a negative feedback system steps up production- the controlled condition is the amount of oxygen delivered to the tissues |
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Term
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Definition
| cellular oxygen deficiency, occurs if too little oxygen enters the blood, and this stimulates the kidneys to increase the release of EPO |
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Term
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Definition
| RBC production falls below RBC destruction |
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Term
| Kidney response to hypoxia |
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Definition
release erythropoietin
speeds up development of proerythroblasts into reticulocytes |
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Term
| Low count in an anemic person might indicate |
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Definition
| shortage of EPO or an inability of the red bone marrow to respond to EPO |
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Term
| High blood cell count might indicate |
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Definition
| recent blood loss or successful iron therapy, or illegal use of artificial EPO by an athlete |
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Term
| Leukocytes have surface proteins, as do other cells, called |
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Definition
| major histocompatibility antigens (MHC), and are unique for each person (except for identical siblings) |
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Term
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Definition
Polymorphonuclear leukocytes (PMNs or Polys).
Nuclei 2 to 5 lobes connected by thin strands.
young cells called band cells because of horseshoe shaped nucleus (band).
Fine, pale lilac practically invisible granules.
Diameter is 10-12 microns.
60 to 70% of circulating WBCs. |
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Term
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Definition
Fastest response of all WBC to bacteria.
Direct actions against bacteria.
release lysozymes which destroy/digest bacteria.
release defensin proteins that act like antibiotics & poke holes in bacterial cell walls destroying them.
release strong oxidants (bleach-like, strong substances) that destroy bacteria. |
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Term
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Definition
Nucleus with 2 or 3 lobes connected by a thin strand.
Large, uniform-sized granules stain orange-red with acidic dyes.
do not obscure the nucleus.
Diameter is 10 to 12 microns.
2 to 4% of circulating WBCs. |
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Term
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Definition
Leave capillaries to enter tissue fluid.
Combat the effects of histamine by releasing histaminase.
slows down inflammation caused by basophils.
Attack parasitic worms.
Phagocytize antibody-antigen complexes. |
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Term
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Definition
Large, dark purple, variable-sized granules stain with basic dyes.
Obscure the nucleus.
Irregular, s-shaped, bilobed nuclei.
Diameter is 8 to 10 microns.
Less than 1% of circulating WBCs. |
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Term
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Definition
Involved in inflammatory and allergy reactions.
Leave capillaries & enter connective tissue.
Similar in function as mast cells.
Release heparin, histamine & serotonin in response to allergic reaction.
heighten the inflammatory response and account for hypersensitivity (allergic) reaction. |
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Term
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Definition
Dark, oval to round nucleus.
Cytoplasm sky blue in color.
amount varies from rim of blue to normal amount.
Small cells 6 - 9 microns in diameter.
Large cells 10 - 14 microns in diameter.
increase in number during viral infections.
20 to 25% of circulating WBCs. |
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Term
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Definition
B cells -
destroy bacteria and their toxins.
in response to the presence of foreign substances called antigens, differentiate into tissue plasma cells that produce antibodies.
T cells -
attack viruses, fungi, transplanted organs, cancer cells & some bacteria.
Natural killer cells (NK) -
attack many different microbes & some tumor cells.
destroy foreign invaders by direct attack. |
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Term
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Definition
-Nucleus is kidney or horse-shoe shaped.
-Largest WBC in circulating blood.
-does not remain in blood long before migrating to the tissues.
-differentiate into macrophages.
-fixed group found in specific tissues.
-alveolar macrophages in lungs.
-kupffer cells in liver.
-wandering group gathers at sites of infection.
-Diameter is 12 - 20 microns.
-Cytoplasm is a foamy blue-gray.
-3 to 8% of circulating WBCs. |
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Term
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Definition
Take longer to get to site of infection, but arrive in larger numbers.
Become wandering macrophages once they leave the capillaries.
Destroy microbes and clean up dead tissue following an infection by phagocytosis. |
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Term
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Definition
Can live for several months or years, but most for only a few days.
Less numerous than RBCs.
5000 to 10,000 cells/µL.
1 WBC for every 700 RBC. |
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Term
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Definition
is a high white blood cell count (↑10,000/µL).
normal response to microbes, strenuous exercise, anesthesia or surgery |
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Term
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Definition
is low white blood cell count (↓5,000/µL).
radiation, shock or chemotherapy (never good) |
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Term
| Only _____ of total WBC population is in circulating blood at any given time |
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Definition
Only 2% of total WBC population is in circulating blood at any given time
rest is in lymphatic fluid, skin, lungs, lymph nodes & spleen |
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Term
| Emigration & Phagocytosis in WBCs |
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Definition
WBCs leave the blood, roll along endothelium, stick to it & squeeze between cells.
adhesion molecules (selectins) help WBCs stick to endothelium.
This is the EC display in response to injury
neutrophils stick to carbohydrates on EC causing them to slow down and roll.
integrins on neutrophils tether them to EC and assist in their transmigration.
Neutrophils & macrophages phagocytize bacteria & debris
and these cells chemotax in response to several factors secreted by cells/microbes |
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Term
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Definition
Detection of changes in numbers of circulating WBCs (percentages of each type).
indicates infection, poisoning, leukemia, chemotherapy, parasites or allergy reaction |
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Term
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Definition
neutrophils 60-70% (up if bacterial infection).
lymphocyte 20-25% (up if viral infection).
monocytes 3 -- 8 % (up if fungal/viral infection).
eosinophil 2 -- 4 % (up if parasite or allergy reaction).
basophil <1% (up if allergy reaction or hypothyroid). |
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Term
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Definition
Thrombopoietin stimulates myeloid stem cells to develop
into megakaryocyte-colony-forming cells that develop into megakaryoblasts
Megakaryoblasts transform into megakaryocytes which fragment.
Each fragment, enclosed by a piece of cell membrane, is a platelet (thrombocyte).
Platelets break off from megakaryocytes in red bone marrow and then enter the blood circulation |
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Term
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Definition
| Normal blood contains 150,000 to 400,000 platelets/µL |
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Term
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Definition
| Platelets help stop blood loss from damaged blood vessels by forming a platelet plug, and their granules also contain substances which aid in clot formation |
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Term
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Definition
| Platelets have a life span of only 5 to 9 days; aged and dead platelets are removed by fixed macrophages in the spleen and liver. |
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Term
| Complete Blood Count (CBC) |
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Definition
Screens for anemia and infection
Total RBC, WBC & platelet counts per µL of whole blood; differential WBC; and hematocrit
The amount of hemoglobin in grams per mL is also determined.
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Term
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Definition
| infants = 14 to 20 g/100mL of blood adult females = 12 to 16 g/100mL of blood adult males = 13.5 to 18g/100mL of blood |
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Term
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Definition
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Term
| Stem cell transplant from bone marrow |
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Definition
Bone marrow transplant replaces diseased red marrow with healthy red marrow in order to establish normal blood cell counts.
Patient’s diseased marrow is destroyed by high doses of chemotherapy or full body radiation just before the transplant.
Healthy marrow is supplied by a donor or the patient when the disease is inactive
Marrow is removed from the iliac crest with a syringe, and injected into the recipient’s vein. The injected marrow migrates to the recipient’s red bone marrow cavities, the stem cells in the marrow multiple and the recipient’s diseased marrow is replaced entirely with health marrow |
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Term
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Definition
patient’s WBC are destroyed and he is now susceptible to infection
donor marrow may produce T cells that attack recipient’s tissue (graft-versus-host disease)
if any of the recipient’s cells survived chemo/radiation, they can attack the donor marrow
recipient must take immunosuppressive drugs for life, which increase the risk of infection, and have bad side effects |
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Term
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Definition
| Stem cells are taken from the umbilical cord shortly after birth and frozen |
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Term
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Definition
a sequence of responses that stops bleeding
quick response and carefully controlled
three mechanism reduce blood loss:
vascular spasm
platelet plug formation
coagulation (blood clotting)
prevents hemorrhage, the loss of a large amount of blood from the vessels.
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Term
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Definition
Damage to blood vessel produces contraction of SMC.
Can reduce blood loss for several hours until other mechanisms can take over
Probably caused by damage to the SMC, by substances released from activated platelets, and by reflexes initiated by pain receptors
Only for small blood vessel or arteriole
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Term
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Definition
Platelets store a lot of substances in granules needed for platelet plug formation:
clotting factors, platelet-derived growth factor (cause proliferation of vascular EC, SM fibers & fibroblasts to repair damaged vessels), and ADP, ATP, Ca2+, serotonin, fibrin-stabilizing factor, & enzymes that produce thromboxane (TBX) A2, lysosomes, and glycogen.
Steps in the process
(1) platelet adhesion
(2) platelet release reaction
(3) platelet aggregation
initially the platelet plug is loose, but then tightens when reinforced by fibrin threads formed during clotting. |
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Term
Step 1 in Platelet Plug Formation:
Platelet Adhesion |
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Definition
| Platelets stick to parts of a damaged bv, such as collagen fibers of connective tissue underlying the damaged EC |
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Term
Step 2 in Platelet Plug Formation:
Platelet Release Reaction |
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Definition
Platelets activated by adhesion.
Extend projections to make contact with each other and begin to release the contents of their vesicles.
Liberated thromboxane A2 & ADP activate nearby platelets.
Serotonin & thromboxane A2 are vasoconstrictors, which decrease blood flow through the injured vessel.
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Term
Step 3 in Platelet Plug Formation:
Platelet Aggregation |
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Definition
Activated platelets stick together and activate new platelets to form a mass called a platelet plug.
Plug reinforced by fibrin threads formed during clotting process |
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Term
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Definition
Blood remains liquid as long as it is contained in vessels, but if it is drawn from the body it will form a gel.
Eventually the gel (clot) separates from the straw-colored liquid (serum).
A clot consists of a network of insoluble protein fibers (fibrin) in which formed elements of blood are trapped.
Clotting or coagulation is a series of chemical reactions that culminates in formation of fibrin threads.
If blood clots too easily, the result is thrombosis (clotting in an undamaged vessel); if blood takes too long to clot, hemorrhage can occur
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Term
| Substances involved in Clotting |
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Definition
| The substances involved in clotting are known as coagulation (clotting) factors, and include Ca2+, enzymes, and platelet-associated molecules |
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Term
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Definition
Clotting can be divided into three
1. formation of prothrombinase (prothrombin activator)
2. conversion of prothrombin into thrombin
3. conversion of soluble fibrinogen into insoluble fibrin
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Term
| Extrinsic Pathway of Blood Clotting |
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Definition
Occurs rapidly- within seconds.
Damaged tissues leak tissue factor (TF; thromboplastin) into bloodstream.
Prothrombinase forms in seconds.
TF is a mixture of lipoproteins and phospholipids released from the surface of damaged cells
In the presence of Ca+2, TF begins a sequence that activates clotting factor X, which when activated, combines with factor V to form prothrombinase
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Term
| Intrinsic Pathway Blood Clotting |
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Definition
Occurs more slowly- requiring several minutes
Activation occurs when:
-endothelium is damaged & platelets come in contact with collagen of blood vessel wall
-trauma to EC cause platelet damage & release of phospholipids
Contact with collagen fibers (or glass of collecting tube) activates factor XII, which begins a series of reactions and eventually activates factor X
Platelet phospholipid and Ca+2 can also participate in activation of factor X
Active factor X combines with factor V to form prothrombinase
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