Chapter 17 Blood Flashcards
What are the three functions of blood?
Distribution, Regulation and Protection
What does blood regulate?
- Body temperature by regulating blood flow to skin and deep organs.
- pH in body tissue. Blood cells act as buffers due to proteins in the blood.
- Adequate Fluid Volume
What does blood protect against?
- Blood loss
2. Defense against infection using white blood cells, antibodies and specialized proteins.
Temperature of blood
104 F
Why is venous and arterial blood different colors?
Differences in hemoglobin content
What is the normal blood pH?
7.4
Normal volume of blood in males/females?
5-6 liters in males / 4-5 liters in females
What is blood composed of?
Plasma and Formed Elements
What is blood plasma composed of?
- 55% whole blood
- 8% plasma proteins
- Other solutes 2 % (gases, hormones, nutrients, wastes)
- 92% water
What makes up formed elements?
- 45% whole blood
- White blood cells and platlets
- Red Blood cells 99%
What two components make up extra cellular fluid (fluid external to cells)?
Plasma and interstitial fluid (fluid that bathes the exterior of cells)
What does plasma resemble? Why?
Interstitial Fluid due to the continual exchange of water, ions and small solutes across capillary walls.
Name the two primary differences between interstitial fluid and plasma
- Concentrations of dissolved proteins in blood are much higher because most plasma proteins cannot cross capillary walls due to shape and size.
- Levels of respiratory gases; blood transports O2 from lungs to body tissue and CO2 away from tissue to lungs.
What are the function of plasma cells? who makes them?
To make antibodies which are proteins.
Lymphocytes
What are antibodies also known as? what part of the blood do they consistute?
immunoglobulin
gamma globulin
Name three plasma proteins.
- Globulin
- Albumins
- Fibrinogen
What is the most abundant plasma protein? Percentage?
Albumin. 60%
Which plasma protein is a major contributor to the osmotic pressure of plasma and what is that pressure known as?
Albumin.
BCOP-Blood colloid osmotic pressure
Name functions of albumin plasma protein
Transport
Act as buffer in plasma
What percentage of plasma protein is Globulin?
36%
What are the functions of globulin
- Immunoglobulin (the most significant gamma globulins)
2. Transport globulins-they bind ions, hormones and lipids for transport.
What percentage of plasma protein is Fibrinogen?
4%
Function of fibrinogen
Blood clotting where fibrin is the result.
What is the difference between plasma and serum?
Plasma contains the clotting factors still present in solution; serum does not. Serum is plasma without the clotting factors which are in the blood clot.
Where are the primary site of hematopoiesis during second to fifth months?
Liver and spleen
Define hematopoiesis
Production of formed elements
How much blood and new cells does the bone marrow turn out each day?
1 ounce of new blood and 100 billion new cells.
What week of embryonic development do blood cells appear in blood stream?
3rd
In early embryonic life, what is the primary site of red blood cell formation?
yolk sac
Where are blood cells at the 8th week of embryonic development?
Embryonic blood cells move out of bloodstream to liver, spleen, thymus and bone marrow where they differentiate into stem cells.
Where is the primary site of blood cell production after the fifth month?
Bone marrow
From what common cell do all formed elements arise?
Hemocytoblast which is a common stem cell.
What two kinds of stem cells arise from hemocytoblast?
- Lymphoid (produces lymphocytes)
2. Myeloid (produce all other formed elements)
What is the technical name of red blood cells?
erythrocyte
How many blood cells does the average adult have?
25 trillion (1/3 of all the cells in the body)
What is the primary role of red blood cells?
Transport of O2, CO2 and respiratory gases
How many red blood cells are in a drop of blood
260 million
What is the normal red blood cell count in males?
4.7-6.1 million cells/mm3
What is the normal red blood cell count in females?
4.2-5.4 million cells/mm3
How do you determine approximate red blood cell count from known hematocrit?
% Hematocrit x 11 = total RBC count x 10e4
Define hematocrit
Percentage of whole blood occupied by red blood cells
What is the normal hematocrit in the adult male
47 +/- 5%
What is the normal hematocrit in adult female
42 +/-5%
What is the hematocrit also known as?
Packed cell volume
What is the very thin layer that lays between the plasma and red blood cells?
White blood and platlets aka the buffy coat.
How do you determine the hematocrit from known hemoglobin value?
Hematocrit = 3 x Hemoglobin value
What is the shape, average diameter and maximum thickness?
Biconcave disc, average diameter 7.5um and maximum thickness 2.5um
Characteristics of red blood cells
stackable (rouleaux) and bend and flex
During which stage of red blood cell formation is hemoglobin actively synthesized.
Formative stages
What are red blood cells missing in the mature state?
nuclei, ribosomes or organelles associated with transport of respiratory gases
Life span of red blood cells?
120 days
Where do red blood cells obtain there energy from?
not mitochondria but anaerobic metabolism of glucose absorbed from plasma.
What is the principal function of hemoglobin?
It is a protein molecule contained in red blood cells that transports oxygen and CO2
What is the shape and contents of a hemoglobin molecule?
Quaternary structure consisting of two alpha chains, two beta chains, iron and heme.
How is oxygen transported via hemoglobin?
O2 binds to iron
How many hemoglobin molecules are there per red blood cell
250 million
What happens to the blood that is not transported via hemoglobin?
it dissolves in plasma
How is CO2 transported via hemoglobin?
CO2 binds to amino acids in the globlin portions of hemoglobin
How much of CO2 transportation is accomplished by hemoglobin?
20%
How much of intracellular proteins is accounted for by hemoglobin? What does the remaining proteins function as?
95%
The remaining function to maintain plasma membrane or promote changes in red blood cell shape.
What are the units hemoglobin reported in?
grams per 100mL of whole blood.
Gms/dl
Gms %
Hgb or Hb
What is the normal range of hemoglobin in adult males?
13-18 Gms %
What is the normal range of hemoglobin in adult females?
12-16 Gms %
How do you determine hemoglobin value from hematocrit value?
Hct/3=Hgb
Define erythropoiesis
red blood cell production
What is the only site of red blood cell production and the primary site of white blood cell production?
red bone marrow
How long is the whole red blood cell production process?
15 days.
What happens during red blood cell production?
erythroblasts synthesize hemoglobin
What supplies do red blood cell production require?
The usual protein, lipids and carbs as well as folic acid, Vitamin B12 and iron.
What stimulates Red Blood Cell Production?
Erythropoietin
Where is Erythropoietin produced?
Kidneys
When does erythropoietin increase?
When peripheral tissues are hypoxic
What is the rate of RBC production
3 million red blood cells per second
How many RBCs are replaced daily?
1% or 250 billion
How does erythropoietin work?
Erythropoietin stimulates stem cells and red blood cells when during a. during anemia b. when blood flow to kidney is decreased c. when O2 to lungs decreases d. when lungs are damaged
What hormone increases EPO production?
testosterone
How does erythropoietin work?
- Increase in cell division rates of erythroblast
2. speeds up maturation of RBCs via hemoglobin synthesis
How much can Red Blood Cells increase by stimulation with erythropoietin?
10X
Define Anemia
Blood has low O2 capacity due to reduction in hemoglobin or hematocrit.
Causes of Anemia
- Insufficient RBC (hemmoragic, hemolytic, aplastic)
- Low hemoglobin conent (iron, vit B12 deficient)
- Abnormal hemoglobin (thalassemias, sickle cell)
Define Polycythemia
abnormal excess of RBCs
Causes of polycythemia
Primary-polycythemia vera
Secondary-Physical Location
Third-Blood Doping
Describe 6 steps of red blood cell life cycle
- Low O2 stimlates kidneys to produce Erythropoietin
- EPO levels rise
- Erythropoiesis in bone marrow
- New Blood cells enter blood stream for 120 days
- RBC engulfed by macrophage of spleen, liver and bone marrow.
- Raw material available in blood for erythrocyte synthesis.
Define Surface antigen
Aka agglutinogens are glycoproteins that are genetically determined
Define Antibodies
Aka agglutins which attack foreign surface antigens in plasma
What percents of population are TYPE O, A,B,AB?
46%, 40%, 10%, 4%
What percent of Americans are Rh positive?
85
Erythroblastosis fetalis/hemolytic disease of newborn
When Rh negative mom gives birth to second Rh positive baby.
Define blood typing
When anti A and anti B serums are added to blood to observe clumping.
Define cross-matching
When you mix doner/recipient RBCs with donor/recipient serum.
What reactions can cross reactions occur
agglutination or hemolysis
What is the main worry in blood transfusion?
Large amounts of free hemoglobin in blood and hemolysis of blood cell
What is the main function of leukocytes
To defend against pathogens
Leukocyte structure
Contain nucei and organelles but no hemoglobin
What is the number of circulating WBCs per RBC
600-700
How many WBCs does a typical microliter of blood have
5000-11000 WBCs
Define Leukocytosis
Greater number of WBCs than normal in peripheral blood due to infection, injury or allergies
Define Leukemia
Clones of unspecialized WBCs.
What are the results of leukemia
Malignant cells crowd out blood resulting in
- anemia
- bleeding problems
- compromised immune problems
Define Leukopenia
Underproduction of WBCs due to drugs, glucocorticoids and bone marrow malignancies
Describe WBC characteristics
Amoebid mvmt, Diapedisis, Chemotaxis, Phagocytosis
Which white blood cell types have non specific defenses
Neutrophil, Eosinophil, Basophil, Monocyte
Which WBC types have specific defenses?
Lymphocytes
List WBC types from highest % of circulating WBC to least %.
Neutrophil (50-70). Lymphocytes (20-40), Monocytes (3-8), Eosinophil (2-4) Basophil (0.5-1)
Which WBC types are granulocytes?
Basophil, Eosinophil, Neutrophil
Function of Basophil
Rush to injury site and release heparin and histamine
Which WBC types have longest and shortest life span?
Shortest Neutrophils
Longest Lymphocytes
Which WBCs are produced and differentiate in bone marrow? Which do not?
Bone Marrow-Neutrophil, Eosinophil, Basophil
Monocyte-differentiate in tissue
Lymphocyte-moves between bone marrow and tissue
Name the types of Lymphocytes and their function
T Cell-direct attack on foreign cells
B Cells-Antibodies in body fluids
Natural Killer-general surveillance
Which WBC type can digest large pathogens
Eosinophils
Which WBC type contains granules that contain lysosomes for digestions and defensins to kill bacteria
Neutrophils
What is the location and name of cells that produce platlets
Megakaryocyte and they are produced in the bone marrow
How long do platlets survive
10 days
How many platlets circulate and how many are stored? Where are they stored?
2/3 circulate, 1/3 stored in spleen
How are platlets regulated?
Hormonally by Thrombopoetin
What is the normal concentration of platlets in blood?
150-400,000/mm3
Thrombocytopenia
platlet deficit
Thrombocytosis
platlet excess
Three phases of homeostasis
Vascular, Platlet and Coagulation Phase
What happens during Vascular Phase
Spasm of smooth muscle wall in response to pain or injury
What happens during platlet phase
Initiates clotting
In normal conditions why wont platelts stick to one another?
Because endothelial cells release Nitric Oxide and Prostocyclin
Name chemicals that platlets release during platlet phase
Thromboxane, ADP, Clotting Factors, Serotonin, Calcium Ions
In coagulation phase, where are all clotting factors manufactured? What are the exceptions?
The liver
Calcium and Thromboxane
Name the 4 pathways of coagulation phase?
- Intrinsic
- Tissue Factor
- Extrinsic
- Common Pathway
Which pathway of coagulation phase is fastest?
Extrinsic
In coagulation phase, Tissue Factor Pathway…which elements when combined lead to factor X?
Tissue Factor + Ca + Tissue Factor Complex
In coagulation phase, Intrinsic Pathway…which elements when combined lead to factor X?
Factor X11 + PF3 + Other Factors
Describe the common pathway after Factor X.
Begin Prothrombinase (turns prothrombin to thrombin), Thrombin converts fibrinogen to fibrin which forms clot.
In addition to fibrinogen, what else does thrombin stimulate?
Tissue Factor and PF3 which stimulate extrinsic and intrinsic pathways.
What two substances in platelets compact clot and vessel?
Actin and Myosin
What two substances in platelets repair defects?
Platelet growth factor and endothelial factor
Define Fibrolysis
When the clot gradually dissolves as the vessel repairs.
How is the clot eroded?
By plasmin which is derived from plasminogen and created by the combination of tPA, Thrombin and Factor XII.
Why doesnt a clot once formed, keep expanding and become unnecessarily large?
- Dilution of clotting factors
- Restriction of Thrombin (which converts)
- Herparin inhibits thrombin and intrinsic pathway
- Action of prostacyclin (inhibits aggregation)
Define Thrombus
A clot that develop and persists in an unbroken vessel predisposed by 1. irregular blood vessel lining 2, slow blood flow 3. heart rhythm disturbances 4. Heart valve damage
Embolus
A clot that breaks away from the site of its formation in a blood vessle or in the heart
Desseminated Intravascular Clotting (DIC)
Widespread clotting occurs in intact blood vessels. Fibrin creates clots and once fibrinogen is used up uncontrolled bleeding results. Seen in septicemia, pregnancy or bad transfusions.
Causes for abnormal bleeding
- platlet deficientcy
- impaired liver function
- Hemophilias (ABC)
- Too much anticoagulant
Drugs that prevent Fibrin from forming
- Heparin
- Low Molecular Weight Heparin
- Coumadin/Warfarin
Drugs that act on fibrin by dissolving strands already formed.
- tPA-Tissue Plasminogen Activator
- Urokinase
- Streptokinase
- Nattokinase
Drugs that act on platlets to reduce stickiness
- Aspirin
- Dipyramidole (Persantine)
- Plavix (clopidogrel)
- IIb/IIa inhibitors