17 Blood Flashcards
What is the hematocrit
Percent of RBC in blood volume
45%
Describe normal blood ph, temp, and volume
7.35-7.45
38*C
5-6 male
4-5 female
What are the 3 main functions of blood
Substance distribution
Regulation of particular substances
Body protection
What does blood transport
Oxygen and nutrients
Metabolic waste to lungs and kidneys
Hormones to target organs
How does blood prevent blood loss
Activating plasma proteins and platelets
Initiate clot formation
How does blood prevent infection
Synthesizing and utilizing antibodies
Activating complement
Activating WBC
What types of substances are in blood plasma
Proteins Waste Organic nutrients Electrolytes Respiratory gases
What makes up 60% of plasma proteins
Albumin
How are blood cells renewed
By red bone marrow
Describe an erythrocytes
Biconcave disc
Anucleate
Filled with hemoglobin
Contain Spectrin in membrane
Describe hemoglobin
Made of globin protein -2 alpha chains -2 beta chains Each bound to heme Each heme has an iron Each iron can bind to oxygen
What is oxyhemoglobin
Hb bound to oxygen
What is deoxyhemoglobin
Hb after oxygen diffuses into tissues
What is carbaminohemoglobin
Hb bound to carbon dioxide
What structural characteristics of RBC contribute to its function
Biconcave shape- huge surface area
More than 97% Hb
ATP is generated anaerobically- doesn’t use o2 it transports
Where does hematopoiesis occur
In red bone marrow
Of axial skeleton and girdles
Epiphytes of humerus / femur
What is the stem cell of all formed elements
Hemocytoblast
What causes tissue hypoxia
Not enough RBC
What Happens with too many RBC
High blood viscosity
What controls erythropoiesis
EPO
What triggers the release if EPO
Low blood oxygen levels from
Decreased RBC
Decreased oxygen availability
Increased tissue demand
Where is EPO released from
What is its target
Kidney/ liver
Red bone marrow
In a clinical setting how does one check for the production of RBC
Blood level reticulocyte count
What are the dietary requirements of erythropoiesis
Nutrients
Iron
Vit B12
Folic acid
Where is iron stored
Hb65%
Liver
Spleen
Bone marrow
How is iron loosely transported
Bound to transferrin
What forms is iron stored in in cells
Ferritin
Hemosiderin
Why do cells need B12 and Folic acid
For DNA synth
Where do macrophages degrade RBC
In the spleen
Describe the process of degrading heme
Iron is salvaged
Heme becomes bilirubin
Liver secretes bilirubin into intestines
Leaves as stercobilin
Describe the process of degrading globin
Broken into amino acids
Define anemia
Blood has low oxygen carry capacity
What types of anemia are caused by insufficient erythrocytes
Hemorrhagic
Hemolytic
Aplastic
What anemia is caused by acute/ chronic blood loss
Hemorrhagic
What anemia is caused by prematurely ruptured RBC
Hemolytic
Via malaria or bad transfusiob
What anemia is caused by destruction/ inhibition of RBMarrow
Aplastic
What anemias are caused by decreased hemoglobin content
Iron deficiency
Pernicious
What anemias are caused by abnormal Hb
Thalassemias
Sickle cell
What is a secondary result of hemorrhagic anemia
Iron deficiency anemia
What is the treatment of pernicious anemia
Injection of B12
Application of nascobal
What 2 things cause iron deficiency anemia
Not enough iron in diet
Unable to absorb iron, damaged intestinal linings
What causes pernicious anemia
Lack of B12
Lack of intrinsic factor for its absorption
What anemia is caused by absent or faulty globin
Thalassemia
RBC deficient in Hb
What anemia. Is caused by abnormal Hb called HbS
Sickle cell
What is wrong with HbS
Single amino acid substitution in the beta chain
What is polycythemia
Too many RBC
What are the 3 types of polycythemia
Polycythemia Vera- cancer
Secondary polycythemia- high altitudes
Blood doping
What level of WBC is normal for infection
11,000
Describe granulocytes
Phil’s
Lobed nuclei
Phagocytic
What do neutrophil granules contain
Peroxidases
Hydrolytic enzymes
Defensins
How do eosinophils lessen allergies
By phagocytizing immune complexes
What are basophils similar to
Mast cells
What does histamine do
Acts as vasodilator and attracts other WBC
Describe agranulocytes
Cytes
Lack granules
Where are most lymphocytes found
In lymphoid tissue
Some circulate in blood
What do macrophages do
Phagocytose
Activate lymphocytes to mount. Immune response
What cell do all leukocytes come from
Hemocytoblasts
Give examples of leukemia
Myelocytic-myeloblasts
Lymphocytic- lymphocytes
What stem cell forms platelets
Hemocytoblasts
What happens with leukemia
Immature WBC in bloodstream
Bone marrow overtaken with cancerous cells
Death from hemorrhage and infections
What cells are platelets fragments of
Megakaryocytes
What keeps platelets inactive
Nitric acid
Prostacyclin
What do platelet granules contain
Thromboxane A
Ca
ADP
Platelet derived growth factor
What are the 3 phases of hemostasis
Vascular spasm
Platelet plug
Coagulation
What 3 things trigger vascular spasms
Direct injury to vascular smooth muscle
Chemicals released by endothelium
Reflexes initiated by local pain receptors
What causes platelets to aggregate
Contact with collagen in the basal lamina
What does Von willebrand factor do
Stabilize platelet plug
What 3 things do platelets in plug release
ADP
Thromboxane A
Calcium
How does ADP help plug form
Makes platelets sticky
How does thromboxane A help platelet plug
Enhance vascular spasm
Platelet aggregation
When is blood changed into a gel
Coagulation
What type of coagulants normally dominate in blood
Anticoagulants
What are the 3 phases of clot formation
Make prothrombin activator
Convert prothrombin to thrombin
Convert fibrinogen into fibrin
What is prothrombinase
Prothrombin activator
Describe the intrinsic pathway of activating factor x
Exposé factor xii to collagen or glass
Describe the extrinsic pathway of activating factor x
Release factor iii aka Tissue factor
from under endothelium
Which is the faster pathway to activate factor x
Extrinsic
What is the role of factor x
To convert prothrombin protein into thrombin enzyme
What is the role of thrombin
To catalyze joining of fibrinogen molecules into fibrin mesh
What is the role of prothrombin activator
To convert prothrombin into thrombin
What is clot retraction
Stabilization of the clot by squeezing serum from fibrin
What does platelet derived growth factor stimulate
Rebuilding of vessel wall
What 3 things help with repair of vessels
PDGF
Fibroblasts- connective patch
VEGF
What does VEGF do
Vascular endothelial growth factor stimulates endothelial cells to restore vessel
Replace connective patch
What 2 things prevent clot from getting to large
Swift removal of clotting factors
Inhibition of activated clotting factors
what inactivates thrombin
Anti thrombin 3
What are the 2 disorders of blood hemostasis
Thromboembolytic disorders
Bleeding disorders
Describe a thrombus
A persisting clot in an unbroken vessel
Can block circulation and cause tissue death
Describe an embolus
A free floating thrombus
Embolism when trapped in vessel too small
What 3 drugs can treat undesirable clots
Aspirin
Heparin
Warfarin
How does aspirin prevent clots
Anti prostaglandin
Anti platelet
Inhibits thromboxane A
How does heparin inhibit clots
Anticoagulant
Inhibits thrombin
Intravenous
How does warfarin inhibit clots
Inhibits factors 6,9, 10, 2
What is thrombocytopenia
When number if circulating platelets is low
From suppression of bone marrie
What does thrombocytopenia cause
Many small hemorrhagic areas
Petechiae
What are hemophilias
What causes them
Deficiency of one clotting factor
Like A8,B9,C11
What is most common hemophilia
Hemophilia A
Lack of factor viii 8
What 2 types if bleeding disorders are there
Hemophilia
Liver issues
What types of things cause liver related bleeding disorders
Vit k deficiency
Hep C
Cirrhosis
Why is liver needed for clotting factor production
Produces bile for digestion of fat
Fat needed for absorption of Vit K
Vit k needed to synth clotting factors
When are whole transfusions given
Substantial blood loss
Thrombocytopenia
When are packed cells given
Anemia treatments
When is plasma or saline given
When low blood volume
What are some examples of plasma expenders
Purified human serum albumin
Plasminate
Dextran
What is another term for RBC antigens
Agglutinogens
What happens when RBC antigens and antibodies mix
Hemolytic reaction
What do transfusion reactions cause
Diminished oxygen carrying
Clumped cells
Ruptured RBC- release Hb into blood
Circulating Hb can cause renal failure
What are the 3 common Rh agglutinogens
C
D
E
When are anti Rh antibodies made
When Rh- person is exposed to Rh+
What happens in hemolytic disease of the newborn
Rh+ sensitize Rh- mom
Antibodies cross placenta and attack Rh+ baby
What drug is used to prevent hemolytic disease of the newborn
rhogam
Prevents sensitization