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50 Cards in this Set
- Front
- Back
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Fluids of the Body
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Cells of the body are serviced by 2 fluids
blood composed of plasma and a variety of cells transports nutrients and wastes interstitial fluid bathes the cells of the body Nutrients and oxygen diffuse from the blood into the interstitial fluid & then into the cells Wastes move in the reverse direction Hematology is study of blood and blood disorders |
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Functions of Blood
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Transportation
O2, CO2, metabolic wastes, nutrients, heat & hormones Regulation helps regulate pH through buffers helps regulate body temperature coolant properties of water vasodilatation of surface vessels dump heat helps regulate water content of cells by interactions with dissolved ions and proteins Protection from disease & loss of blood |
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Properties of Blood
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Adults have 4-6 L of blood
plasma, a clear extracellular fluid formed elements (blood cells and platelets) Properties of viscosity (resistance to flow) Thicker (more viscous) than water and flows more slowly than water Temperature of 100.4 degrees F pH 7.4 (7.35-7.45) 8 % of total body weight Blood volume 5 to 6 liters in average male 4 to 5 liters in average female hormonal negative feedback systems maintain constant blood volume and osmotic pressure molarity of dissolved particles) if too high, fluid absorption into the blood causes high BP if too low, fluid remains in the tissues causing edema one cause is deficiency of plasma protein due to diet or disease |
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Techniques for Blood Sampling
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Venipuncture
sample taken from vein with hypodermic needle & syringe median cubital vein (see page 717) why not stick an artery? less pressure closer to the surface Finger or heel stick common technique for diabetics to monitor daily blood sugar method used for infants |
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Components of Blood
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Hematocrit
55% plasma 45% cells 99% RBCs < 1% WBCs and platelets |
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Plasma and Plasma Proteins
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Plasma is a mixture of water (>90%), proteins (7%), enzymes, nutrients, wastes, hormones, electrolytes, and gases (2% total)
if allowed to clot, what remains is called serum 3 major categories of plasma proteins albumins are most abundant plasma protein contributes to viscosity and osmolarity and influences blood pressure, flow and fluid balance globulins (antibodies) provide immune system defenses alpha, beta and gamma globulins fibrinogen is precursor of fibrin threads that help form blood clots All plasma proteins formed by liver except globulins (produced by plasma cells descended from B lymphocytes) |
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Non-Protein Components of Plasma
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Plasma contains nitrogenous compounds
amino acids from dietary protein or tissue breakdown nitrogenous wastes(urea) are toxic end products of catabolism normally removed from the blood by the kidneys Nutrients (glucose, vitamins, fats, minerals, etc) Some O2 and CO2 are transported in plasma Many electrolytes are found in plasma sodium makes up 90% of plasma cations accounting for more of blood’s osmolarity than any other solute |
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Formed Elements of Blood
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Red blood cells ( erythrocytes )
White blood cells ( leukocytes ) granular leukocytes neutrophils eosinophils basophils agranular leukocytes lymphocytes = T cells, B cells, and natural killer cells monocytes Platelets (special cell fragments) |
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Hematocrit
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Percentage of blood occupied by cells
female normal range 38 - 46% (average of 42%) male normal range 40 - 54% (average of 46%) testosterone Anemia not enough RBCs or not enough hemoglobin Polycythemia too many RBCs (over 65%) dehydration, tissue hypoxia, blood doping in athletes |
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Blood Doping
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Injecting previously stored RBC’s before an athletic event
more cells available to deliver oxygen to tissues Dangerous increases blood viscosity forces heart to work harder Banned by Olympic committee |
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Blood Cell Production (Hemopoeisis)
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Most cells need continual replacement due to life spans of hours to weeks
Hemopoietic tissues produce blood cells yolk sac in vertebrate embryo produce stem cells that colonize fetal bone marrow, liver, spleen & thymus liver stops producing blood cells at birth, but spleen and thymus remain involved with WBC production lymphoid hemopoiesis occurs in widely distributed lymphoid tissues (thymus, tonsils, lymph nodes, spleen & peyers patches in intestines) red bone marrow produces RBCs, WBCs and platelets stem cells called hemocytoblasts multiply continually & are pluripotent (capable of differentiating into multiple cell lines) committed cells are destined to continue down one specific cell line In adults only in flatbones like sternum, ribs, skull, pelvis, head of femur and humerus Stimulated by erythropoietin, thrombopoietin & colony-stimulating factors (CSFs) |
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Stages of Blood Cell Formation
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Pluripotent stem cells
.1% of red marrow cells replenish themselves as they differentiate into either myeloid or lymphoid stem cells Myeloid stem cell line of development continues: progenitor cells(colony-forming units) no longer can divide and are specialized to form specific cell types example: CFU-E develops eventually into only red blood cells next generation is blast cells have recognizable histological characteristics develop within several divisions into mature cell types Lymphoid stem cell line of development pre-B cells & prothymocytes finish their develop into B & T lymphocytes in the lymphatic tissue after leaving the red marrow |
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Hemopoeitic Growth Factors
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Regulate differentiation & proliferation
Erythropoietin (EPO) produced by the kidneys increase RBC precursors Thrombopoietin (TPO) hormone from liver stimulates platelet formation Cytokines are local hormones of bone marrow produced by some marrow cells to stimulate proliferation in other marrow cells colony-stimulating factor (CSF) & interleukin stimulate WBC production |
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Medical Uses of Growth Factors
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Available through recombinant DNA technology
recombinant erythropoietin (EPO) very effective in treating decreased RBC production of end-stage kidney disease other products given to stimulate WBC formation in cancer patients receiving chemotherapy which kills bone marrow granulocyte-macrophage colony-stimulating factor granulocyte colony stimulating factor thrombopoietin helps prevent platelet depletion during chemotherapy |
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Erythrocytes (Red Blood Cell)
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New RBC’s enter circulation at the rate of 2 million/second
Disc-shaped cell with thick rim 7.5 M diameter & 2.0 m thick at rim Major function is gas transport lost all organelles during maturation so has increased surface area/volume ratio increases diffusion rate of substances in & out of cell 33% of cytoplasm is hemoglobin (Hb) O2 delivery to tissue and CO2 transport back to lungs contains enzyme, carbonic anhydrase (CAH) produces carbonic acid from CO2 and water important role in gas transport & pH balance |
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Erythrocytes Production
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Erythropoiesis produces 2.5 million RBCs/second from stem cells (hemocytoblasts) in bone marrow
First committed cell is proerythroblast has receptors for erythropoietin (EPO) from kidneys Erythroblasts multiply & synthesize hemoglobin Normoblasts discard their nucleus to form a reticulocyte named for fine network of endoplasmic reticulum enters bloodstream as 0.5 to 1.5% of circulating RBCs Development takes 3-5 days & involves reduction in cell size, increase in cell number, synthesis of hemoglobin & loss of nucleus |
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Normal Reticulocyte Count
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Should be .5 to 1.5% of the circulating RBC’s
Low count in an anemic person might indicate bone marrow problem leukemia, nutritional deficiency or failure of red bone marrow to respond to erythropoietin stimulation High count might indicate recent blood loss or successful iron therapy |
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Erythrocyte Homeostasis
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Classic negative feedback control
drop in RBC count causes hypoxemia to kidneys EPO production stimulation of bone marrow RBC count in 3-4 days Stimulus for erythropoiesis low levels of atmospheric O2 increase in exercise hemorrhaging |
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RBC Life Cycle
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RBCs live only 120 days
wear out from bending to fit through capillaries no repair possible due to lack of organelles Worn out cells removed by fixed macrophages in spleen & liver Breakdown products are recycled |
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Nutritional Needs for Erythropoeisis
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Iron is key nutritional requirement for erythropoiesis
lost daily through urine, feces, and bleeding men 0.9 mg/day and women 1.7 mg/day low absorption rate requires consumption of 5-20 mg/day dietary iron in 2 forms: ferric (Fe+3) & ferrous (Fe+2) stomach acid converts Fe+3 to absorbable Fe+2 gastroferritin from stomach binds Fe+2 & transports it to intestine absorbed into blood & binds to transferrin to travel bone marrow uses to make hemoglobin, muscle used to make myoglobin and all cells use to make cytochromes in mitochondria liver binds surplus to apoferritin to create ferritin for storage B12 & folic acid (for rapid cell division) and C & copper for cofactors for enzymes synthesizing RBCs |
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Recycling of Hemoglobin
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In macrophages of liver or spleen
globin portion broken down into amino acids & recycled heme portion split into iron (Fe+3) and biliverdin (green pigment) |
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Fate of Components of Heme
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Iron(Fe+3)
transported in blood attached to transferrin protein stored in liver, muscle or spleen attached to ferritin or hemosiderin protein in bone marrow being used for hemoglobin synthesis Biliverdin (green) converted to bilirubin (yellow) bilirubin secreted by liver into bile converted to urobilinogen then stercobilin (brown pigment in feces) by bacteria of large intestine if reabsorbed from intestines into blood is converted to a yellow pigment, urobilin and excreted in urine |
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Hemoglobin Structure
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Hemoglobin consists of 4 protein chains called globins (2 alpha & 2 beta)
Each protein chain is conjugated with a heme group which binds oxygen to ferrous ion (Fe+2) Hemoglobin molecule can carry four O2 Fetal hemoglobin has gamma instead of beta chains |
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Transport of O2, CO2 and Nitric Oxide
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Each hemoglobin molecule can carry 4 oxygen molecules from lungs to tissue cells
Hemoglobin transports 23% of total CO2 waste from tissue cells to lungs for release combines with amino acids in globin portion of Hb Hemoglobin transports nitric oxide & super nitric oxide helping to regulate BP hemoglobin picks up nitric oxide (NO) & super nitric oxide (SNO)& transport it to & from the lungs NO causing vasodilation is released in the lungs due to CO2 release NO causing vasodilation is released in the tissues due to O2 release |
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Erythrocytes and Hemoglobin
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RBC count & hemoglobin concentration indicate the amount of oxygen the blood can carry
hematocrit(packed cell volume) is % of blood composed of cells men 42-52% cells; women 37-48% cells hemoglobin concentration of whole blood men 13-18g/dL; women 12-16g/dL RBC count men 4.6-6.2 million/L; women 4-2-5.4 million/L Values are lower in women androgens stimulate RBC production women have periodic menstrual losses |
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Erythrocyte Disorders
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Polycythemia is an excess of RBC
primary polycythemia is due to cancer of erythropoietic cell line in the red bone marrow RBC count as high as 11 million/L; hematocrit of 80% secondary polycythemia from dehydration, emphysema, high altitude, or physical conditioning RBC count only up to 8 million/L Dangers of polycythemia increased blood volume, pressure and viscosity can lead to embolism, stroke or heart failure |
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Anemia: is it deficiency of Hemoglobin or RBCs?
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Causes of anemia
inadequate erythropoiesis or hemoglobin synthesis inadequate vitamin B12 from poor nutrition or lack of intrinsic factor from glands of the stomach (pernicious anemia) iron-deficiency anemia kidney failure & insufficient erythropoietin hormone aplastic anemia is complete cessation (cause unknown) hemorrhagic anemias from loss of blood hemolytic anemias from RBC destruction Effects of anemia tissue hypoxia and necrosis (short of breath & lethargic) low blood osmolarity (tissue edema) low blood viscosity (heart races & pressure drops) |
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Sickle-Cell Anemia
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Genetic defect in hemoglobin molecule (Hb-S) that changes 2 amino acids
at low very O2 levels, RBC is deformed by changes in hemoglobin molecule within the RBC sickle-shaped cells rupture easily = causing anemia & clots Found among populations in malaria belt Mediterranean Europe, sub-Saharan Africa & Asia HbS gene persists despite harmful effects increased resistance to malaria because RBC membranes leak K+ & lowered levels of K+ kill the parasite infecting the red blood cells (heterozygote advantage) |
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WBC Anatomy and Types
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All WBCs (leukocytes) have a nucleus and no hemoglobin
Granular or agranular classification based on presence of cytoplasmic granules made visible by staining granulocytes are neutrophils, eosinophils or basophils agranulocytes are monocyes or lymphocytes |
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Leukocyte Production (Leukopoeisis)
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Committed cell types -- B & T progenitors and granulocyte-macrophage colony-forming units
possess receptors for colony-stimulating factors released by mature WBCs in response to infections RBC stores & releases granulocytes & monocytes Some lymphocytes leave bone marrow unfinished go to thymus to complete their development (T cells) Circulating WBCs do not stay in bloodstream granulocytes leave in 8 hours & live 5 days longer monocytes leave in 20 hours, transform into macrophages and live for several years WBCs providing long-term immunity last decades |
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Neutrophils (Granulocytes)
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Polymorphonuclear Leukocytes or Polys
Nuclei = 2 to 5 lobes connected by thin strands older cells have more lobes 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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Eosinophils (Granulocytes)
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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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Basophils (Granulocytes)
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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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Lymphocytes (Agranulocytes)
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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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Monocytes (Agranulocytes)
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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% o circulating WBCs |
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WBC Physiology
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Less numerous than RBCs
5000 to 10,000 cells per drop of blood 1 WBC for every 700 RBC Leukocytosis is a high white blood cell count microbes, strenuous exercise, anesthesia or surgery Leukopenia is low white blood cell count radiation, shock or chemotherapy 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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Emigration and Phagocytosis of WBC
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WBCs roll along endothelium, stick to it & squeeze between cells.
adhesion molecules (selectins) help WBCs stick to endothelium displayed near site of injury molecules (integrins) found on neutrophils assist in movement through wall Neutrophils & macrophages phagocytize bacteria & debris chemotaxis of both kinins from injury site & toxins |
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Neutrophil Functions
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60-70%
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 chemicals ) that destroy bacteria ↑ in bacterial infections |
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Monocyte Functions
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8%
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 ↑ in viral infections and inflammation |
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Basophil Function
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<1%
Involved in inflammatory and allergy reactions Leave capillaries & enter connective tissue as mast cells Release heparin, histamine & serotonin heighten the inflammatory response and account for hypersensitivity (allergic) reaction ↑ in chicken pox, diabetes, autoimmune disorders, hypersensitivities (allergies) |
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Neutrophils (Granulocytes)
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Polymorphonuclear Leukocytes or Polys
Nuclei = 2 to 5 lobes connected by thin strands older cells have more lobes 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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Eosinophils (Granulocytes)
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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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Basophils (Granulocytes)
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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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Lymphocytes (Agranulocytes)
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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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Monocytes (Agranulocytes)
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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% o circulating WBCs |
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WBC Physiology
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Less numerous than RBCs
5000 to 10,000 cells per drop of blood 1 WBC for every 700 RBC Leukocytosis is a high white blood cell count microbes, strenuous exercise, anesthesia or surgery Leukopenia is low white blood cell count radiation, shock or chemotherapy 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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Emigration and Phagocytosis of WBC
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WBCs roll along endothelium, stick to it & squeeze between cells.
adhesion molecules (selectins) help WBCs stick to endothelium displayed near site of injury molecules (integrins) found on neutrophils assist in movement through wall Neutrophils & macrophages phagocytize bacteria & debris chemotaxis of both kinins from injury site & toxins |
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Neutrophil Functions
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60-70%
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 chemicals ) that destroy bacteria ↑ in bacterial infections |
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Monocyte Functions
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8%
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 ↑ in viral infections and inflammation |
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Basophil Function
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<1%
Involved in inflammatory and allergy reactions Leave capillaries & enter connective tissue as mast cells Release heparin, histamine & serotonin heighten the inflammatory response and account for hypersensitivity (allergic) reaction ↑ in chicken pox, diabetes, autoimmune disorders, hypersensitivities (allergies) |
