Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Blood basic facts final


Published on

blood introduction

Published in: Business, Technology
  • Be the first to comment

Blood basic facts final

  1. 1. introduction BLOOD Dr Alamzeb MBBS M.Phil Assistant Professor
  2. 2.
  3. 3. Dr Alamzeb MBBS M.Phil Assistant Professor
  4. 4. Physiology is <ul><li>the study of the function of all plants and animals in their normal state. </li></ul><ul><li>an integrative science </li></ul>Figure 1-1: Levels of organization and the related fields of study
  5. 5. Review Levels of Organization
  6. 6. Human Physiology. In human physiology, we attempt to explain the specific characteristics and mechanisms of the human body that make it a living being. <ul><li>The goal of physiology is to explain the physical and chemical factors that are responsible for the origin, development, and progression of life. </li></ul>
  7. 7. Organ Systems <ul><li>operate as integrated units </li></ul><ul><li>How many? Can you list them? </li></ul><ul><li>Examples: </li></ul><ul><li>Regulation of </li></ul><ul><li>Plasma calcium concentration </li></ul><ul><li>Blood pressure etc. </li></ul>
  8. 8. Function and Process: <ul><li>What is purpose or function? Why does something exist? Why does it need to be done? </li></ul><ul><li>What are processes involved? </li></ul><ul><li> How does something work? </li></ul>
  9. 9. <ul><li>How do we breathe? </li></ul><ul><li>How does blood flow? </li></ul><ul><li>How do RBCs transport O 2 ? </li></ul><ul><li>Why do we breathe? </li></ul><ul><li>Why does blood flow? </li></ul><ul><li>Why do RBC transport O 2 ? </li></ul>Distinguish between Process & Function Integrate both for complete picture!
  10. 10. Key Themes in Physiology: <ul><li>Homeostasis </li></ul><ul><ul><li>Body systems work together (Integration of function) </li></ul></ul><ul><ul><li>Internal vs. external failure of homeostasis </li></ul></ul><ul><li>Communication and movement across cell membranes </li></ul><ul><ul><li>Vital to integration & homeostasis </li></ul></ul><ul><ul><li>Cells communicate with other cells, tissues & organs </li></ul></ul>
  11. 11. Energy Flow and Law of Mass Balance All living processes require constant input of energy Where from? - How is it stored? How is it used to do work? Total amount of substance in body = intake + production - output What substances are maintained through law of mass balance? Major routes for output? Major routes for input?
  12. 12. What is Blood? <ul><li>A dynamic,  life-sustaining solution in animals with closed circulatory systems </li></ul><ul><li>containing </li></ul><ul><li>1. ions,, nutrients, waste products, hormones, other substances, </li></ul><ul><li>2. cells.   </li></ul><ul><li>Blood cells and platelets - are suspended in plasma. </li></ul>
  13. 13. Basic facts <ul><li>One of body organ </li></ul><ul><li>Fluid in nature </li></ul><ul><li>Red in color </li></ul><ul><li>Total circulating blood volume is about 8% of body weight </li></ul><ul><li>5.6 liter in 70 Kg man </li></ul><ul><li>(4 to 5 liters in normal Female & 5-6 liters in normal male ) </li></ul><ul><li>About 55% of this volume is plasma </li></ul><ul><li>Connective tissue in nature </li></ul>Dr Alamzeb MBBS M.Phil
  14. 14. A speck of blood (1 cu mm)
  15. 15. <ul><li>A speck of blood (1 cu mm) the size of this       contains 5 million RBCs, 300,000 platelets, and 7,000 white blood cells. </li></ul>Dr Alamzeb MBBS M.Phil
  16. 16. Dr Alamzeb MBBS M.Phil Blood is the most commonly tested part of the body, Screening, Diagnosis & prognosis of diseases
  17. 17. Easily accessible
  18. 18. Easily obtainable Dr Alamzeb MBBS M.Phil
  19. 19. Easily testable Dr Alamzeb MBBS M.Phil
  20. 20. <ul><li>It is truly the river of life. </li></ul>Every cell in the body gets its
  21. 21.
  22. 22. If we take some blood, prevented from clotting, in a centrifuge, after centrifugation we have this result.
  23. 23. Let us understand the composition of the sedimented blood:
  24. 24. Composition of Blood Blood consist of 1 Red cell 2 White cell 3 Platelets 4 Plasma – in which the above elements are suspended Plasma is the liquid component. which contain soluble fibrinogen Serum is what remains after the formation fibrin clot Dr Alamzeb MBBS M.Phil
  25. 25. BLOOD <ul><li>Your circulatory system contains about 5 liters of the most remarkable fluid on earth, </li></ul><ul><li>traveling through 65,000 miles(104650)Kms of blood vessels to carry oxygen and nutrients to every one of your 100 trillion cells, </li></ul><ul><li>and remove waste products from them. </li></ul><ul><li>45% of the volume is red blood cells (RBCs) which make round trips to your big toe about every 20 seconds, </li></ul><ul><li>flowing through capillaries just 1/10th the diameter of a human hair where the transfer takes small that only one RBC at a time can wriggle through. </li></ul>Dr Alamzeb MBBS M.Phil
  26. 26. BLOOD. Blood is also vital to maintain a stable body temperature by varying the amount of blood to different areas of the body. To do all this, the heart pumps about 2,000 gallons (9100 liters) of blood per day; its valves operate some 5000 times per hour , and it never stops for maintenance...not even once! The Bible said a long time ago that &quot; the life of the flesh is in the blood .&quot; Dr Alamzeb MBBS M.Phil
  27. 27. RBCs Dr Alamzeb MBBS M.Phil
  28. 28. <ul><li>Red blood cells are the most common type of blood cell and the principal means of delivering oxygen from the lungs to body tissues </li></ul><ul><li>Red blood cells are also known as RBCs or erythrocytes (from Greek erythros for &quot;red&quot; and kytos for &quot;hollow&quot;, with cyte translated as &quot;cell&quot;). </li></ul><ul><li>A schistocyte is a red blood cell undergoing fragmentation, or a fragmented part of a red blood cell. </li></ul>RED BLOOD CELLS Dr Alamzeb MBBS M.Phil
  29. 29. Dr Alamzeb MBBS M.Phil
  30. 30. RED BLOOD CELLS Dr Alamzeb MBBS M.Phil
  31. 31. <ul><li>The red color of erythrocytes is due to the heme group of hemoglobin. </li></ul><ul><li>The blood plasma is straw-colored alone, but the red blood cells change colors due to the state of the hemoglobin: </li></ul><ul><li>when combined with oxygen the resulting oxyhemoglobin is scarlet </li></ul><ul><li>and when oxygen has been released, the resulting deoxyhemoglobin is darker, appearing bluish through the blood vessel walls. </li></ul>Dr Alamzeb MBBS M.Phil
  32. 32. <ul><li>Erythrocytes in mammals are anucleate when mature, meaning that they don't have a cell nucleus and thus no DNA . </li></ul><ul><li>In comparison, the erythrocytes of nearly all other vertebrates have nuclei; the only known exception is salamanders . </li></ul><ul><li>Mammalian erythrocytes also lose their other organelles including their mitochondria and produce energy by fermentation , via glycolysis of glucose followed by lactic acid production. </li></ul>Dr Alamzeb MBBS M.Phil
  33. 33. <ul><li>In large blood vessels, red blood cells sometimes occur as a stack </li></ul><ul><li>flat side next to flat side. This is known as rouleaux formation , </li></ul><ul><li>it occurs more often if the levels of certain serum proteins are elevated, as for instance during inflammation . </li></ul>ROUL EAUX FORMATION RED BLOOD CELLS
  34. 34. RED BLOOD CELLS Dr Alamzeb MBBS M.Phil
  35. 35. Concentration of Red Blood Cells in the Blood <ul><li>Normal value Male 52,00000 </li></ul><ul><li>Or 5.2 million per cubic millimeter </li></ul><ul><li>Normal value Female 47,00000 </li></ul><ul><li>Or 4.7 million per cubic millimeter </li></ul><ul><li>± 300000 </li></ul><ul><li>40 to 45 % of the blood volume </li></ul><ul><li>One drop of blood = 1cmm </li></ul>Dr Alamzeb MBBS M.Phil
  36. 36. Shape of RBCs <ul><li>Mammalian erythrocytes are bi co ncave disks: flattened and depressed in the center, </li></ul>Dr Alamzeb MBBS M.Phil
  37. 37. Size of RBCs <ul><li>RBCs having a mean diameter of approximately 8 microns </li></ul>Dr Alamzeb MBBS M.Phil
  38. 38. Thickness <ul><li>2 microns at thickest point </li></ul>Dr Alamzeb MBBS M.Phil
  39. 39. Size at thin point 1 micron at thinnest point The average volume of the red blood cell is 90 to 95 cubic micrometers. Dr Alamzeb Dr Alamzeb MBBS M.Phil
  40. 40.
  41. 41. Thickness continue A sheet of paper is approximately 75 micron thick Therefore 10 Erythrocytes could be aligned side by side across the edge of a sheet paper Dr Alamzeb MBBS M.Phil
  42. 42. Shape of RBCs Under Microscope Red blood cells (erythrocytes) shown above in a stained slide. Note how they stain darker at the edges than in the middle reflecting their biconcave shape. Dr Alamzeb MBBS M Phil
  43. 43. Appearance under microscope Red blood cells (erythrocytes) shown in a stained slide. Note how they stain darker at the edges than in the middle reflecting their biconcave shape.
  44. 44. Concentration of Red Blood Cells in the Blood <ul><li>In normal men, the average number of red blood cells per cubic millimeter is 5,200,000 (±300,000); </li></ul><ul><li>in normal women, it is 4,700,000 (±300,000). </li></ul><ul><li>Persons living at high altitudes have greater numbers of red blood cells. </li></ul>Dr Alamzeb MBBS M.Phil
  45. 45. Quantity of Hemoglobin in the Cells. <ul><li>Red blood cells have the ability to concentrate hemoglobin in the cell fluid up to about 34 grams in each 100 milliliters of cells. </li></ul><ul><li>The concentration does not rise above this value, because this is the metabolic limit of the cell's hemoglobin-forming mechanism. </li></ul><ul><li>Furthermore, in normal people, the percentage of hemoglobin is almost always near the maximum in each cell. </li></ul><ul><li>However, when hemoglobin formation is deficient, the percentage of hemoglobin in the cells may fall considerably below this value, and the volume of the red cell may also decrease because of diminished hemoglobin to fill the cell. </li></ul>
  46. 46. <ul><li>When the hematocrit (the percentage of blood that is cells-normally, 40 to 45 per cent) and the quantity of hemoglobin in each respective cell are normal, the whole blood of men contains an average of 15 grams of hemoglobin per 100 milliliters of cells; </li></ul><ul><li>for women, it contains an average of 14 grams per 100 milliliters. </li></ul>Dr Alamzeb MBBS M.Phil
  47. 47. oxygen carrying capacity <ul><li>Each gram of pure hemoglobin is capable of combining with 1.34 milliliters of oxygen. </li></ul><ul><li>Therefore, in a normal man, a maximum of about 1.34*15 = 20 milliliters of oxygen can be carried in combination with hemoglobin in each 100 milliliters of blood, </li></ul><ul><li>And in a normal woman,1.3*14 = 19 milliliters of oxygen can be carried. </li></ul>Dr Alamzeb MBBS M.Phil
  48. 48. Total surface area <ul><li>The total surface area of the RBCs is about 3800 square meters, </li></ul><ul><li>2000 time greater than the total body surface </li></ul>Dr Alamzeb MBBS M.Phil
  49. 49. Characteristic <ul><li>The shape of RBCs can change remarkably as the cells pass through capillaries. </li></ul><ul><li>Actually RBC is like such a BAG that can be deformed into almost any shape </li></ul><ul><li>The cell has great excess of cell membrane for the quantity of material in side, deformities does not rupture the membrane </li></ul>Dr Alamzeb MBBS M.Phil
  50. 50. Change of shape As you can see by the above photomicrograph red blood cells in life are highly deformable and are able to squeeze through minute gaps.
  51. 51. Dr Alamzeb MBBS M.Phil
  52. 52. Life History Of Erythrocytes <ul><li>Under normal condition 2.5 million erythrocytes are destroyed every second </li></ul><ul><li>This amount seems staggering loss of RBCs </li></ul><ul><li>Until it is realized that the loss represent only 0.00001% of the total 25 trillion RBCs contained in normal adult circulation </li></ul><ul><li>Further more those 2.5 million RBCs are replaced by the production of an equal number of RBCs every second </li></ul>Dr Alamzeb MBBS M.Phil
  53. 53. Life span <ul><li>The RBCs lack a nucleus so it has no power of repair & reproduction. </li></ul><ul><li>It days are strictly numbered </li></ul><ul><li>Average life span is 120 days </li></ul><ul><li>It has been calculated that each RBC travels 175 miles in the course its comparatively short life </li></ul>Dr Alamzeb MBBS M.Phil
  54. 54. production Dr Alamzeb MBBS M.Phil break down Functions Of RBCs
  55. 55. Haematopoiesis <ul><li>Haematopoiesis is an active process which maintain normal number of circulating blood cell & respond rapidly to increased demands such as bleeding or infection </li></ul>Dr Alamzeb MBBS M.Phil
  56. 56. Erythropoiesis <ul><li>Erythropoiesis is an active process which maintain normal number of circulating red blood cell & respond rapidly to increased demands such as bleeding or hypoxia </li></ul>
  57. 57. Areas of the Body That Produce Red Blood Cells. <ul><li>In the early weeks of embryonic life, primitive, nucleated red blood cells are produced in the yolk sac. </li></ul><ul><li>During the middle trimester of gestation, the liver is the main organ for production of red blood cells, but reasonable numbers are also produced in the spleen and lymph nodes. </li></ul><ul><li>Then, during the last month or so of gestation and after birth, red blood cells are produced exclusively in the bone marrow . </li></ul>Dr Alamzeb MBBS M.Phil
  58. 58. Produce of Red Blood Cells by bone marrow. <ul><li>The bone marrow of essentially all bones produces red blood cells until a person is 5 years old . </li></ul><ul><li>The marrow of the long bones, except for the proximal portions of the humeri and tibiae, becomes quite fatty and produces no more red blood cells after about age 20 years. </li></ul><ul><li>Beyond this age, most red cells continue to be produced in the marrow of the membranous bones, such as the vertebrae, sternum, ribs, and ilia. </li></ul><ul><ul><ul><ul><ul><li>Even in these bones, the marrow becomes less productive as age increases. </li></ul></ul></ul></ul></ul>
  59. 59. <ul><li>As children, most of our bones produce blood. </li></ul><ul><li>As we age this gradually diminishes to just the bones of the spine (vertebrae), breastbone (sternum), ribs, pelvis and small parts of the upper arm and leg . </li></ul><ul><li>Bone marrow that actively produces blood cells is called red marrow , and bone marrow that no longer produces blood cells is called yellow marrow . </li></ul>Dr Alamzeb MBBS M.Phil
  60. 60. Pluripotential Hematopoietic stem cell <ul><li>All blood cells (RBCs, WBCs and platelets) in the bone marrow come from the same type of cell, called the </li></ul><ul><li>pluripotential hematopoietic stem cell </li></ul><ul><li>This group of cells has the potential to form any of the different types of blood cells and also to reproduce itself. </li></ul><ul><li>As these cells reproduce, a small portion of them remains exactly like the original pluripotential cells and is retained in the bone marrow to maintain a supply of these, </li></ul>Dr Alamzeb MBBS M.Phil
  61. 61. Committed stem cells <ul><li>The different committed stem cells, when grown in culture, will produce colonies of specific types of blood cells. </li></ul><ul><li>A committed stem cell that produces erythrocytes is called a colony-forming unit-erythrocyte, and the abbreviation CFU-E is used to designate this type of stem cell. </li></ul><ul><li>Likewise, colony-forming units that form granulocytes and monocytes have the designation CFU-GM, and so forth. </li></ul>
  62. 62.
  63. 63. Growth inducers <ul><li>Growth and reproduction of the different stem cells are controlled by multiple proteins called growth inducers. </li></ul><ul><li>Four major growth inducers have been described. </li></ul><ul><li>One of these, interleukin-3, promotes growth and reproduction of virtually all the different types of committed stem cells, </li></ul><ul><li>whereas the others induce growth of only specific types of cells. </li></ul>
  64. 64. Differentiation Inducers. <ul><li>The growth inducers promote growth but not differentiation of the cells. This is the function of another set of proteins called differentiation inducers. </li></ul><ul><li>Each of these causes one type of committed stem cell to differentiate one or more steps toward a final adult blood cell. </li></ul>
  65. 65.
  66. 66. <ul><li>Formation of the growth inducers and differentiation inducers is itself controlled by factors outside the bone marrow. </li></ul><ul><li>For instance, in the case of erythrocytes (red blood cells), exposure of the blood to low oxygen for a long time results in growth induction, differentiation, and production of greatly increased numbers of erythrocytes </li></ul><ul><li>In the case of some of the white blood cells, infectious diseases cause growth, differentiation, and eventual formation of specific types of white blood cells that are needed to combat each infection. </li></ul>
  67. 67. Stages of Differentiation of Red Blood Cells <ul><li>The first cell that can be identified as belonging to the red blood cell series is the proerythroblast, </li></ul><ul><li>Under appropriate stimulation, large numbers of these cells are formed from the CFU-E stem cells. </li></ul>
  68. 68. <ul><li>Once the proerythroblast has been formed, it divides multiple times, eventually forming many mature red blood cells. The first-generation cells are called basophil erythroblasts </li></ul><ul><li>because they stain with basic dyes; the cell at this time has accumulated very little hemoglobin. </li></ul><ul><li>In the succeeding generations, the cells become filled with hemoglobin to a concentration of about 34 per cent, the nucleus condenses to a small size, and its final remnant is absorbed or extruded from the cell. </li></ul><ul><li>At the same time, the endoplasmic reticulum is also reabsorbed. The cell at this stage is called a reticulocyte because it still contains a small amount of basophilic material, consisting of remnants of the Golgi apparatus, mitochondria, and a few other cytoplasmic organelles. </li></ul><ul><li>During this reticulocyte stage, the cells pass from the bone marrow into the blood capillaries by diapedesis (squeezing through the pores of the capillary membrane). </li></ul>
  69. 69. <ul><li>The remaining basophilic material in the reticulocyte normally disappears within 1 to 2 days, and the cell is then a mature erythrocyte. </li></ul>
  70. 70. <ul><li>The proliferation & differentiation of stem cells are under the control of growth factors produced by several cells including stromal cells & lymphocytes. </li></ul><ul><li>These growth factors binds to specific receptors on the cell surface , promote proliferation,differention ,survival & functions of mature cells </li></ul>Dr Alamzeb MBBS M.Phil
  71. 71. Regulation of Red Blood Cell Production-Role of Erythropoietin <ul><li>The total mass of red blood cells in the circulatory system is regulated within narrow limits, so that </li></ul><ul><li>(1) an adequate number of red cells is always available to provide sufficient transport of oxygen from the lungs to the tissues, yet </li></ul><ul><li>(2) the cells do not become so numerous that they impede blood flow. </li></ul>
  72. 72. Tissue Oxygenation Is the Most Essential Regulator of Red Blood Cell Production. <ul><li>Any condition that causes the quantity of oxygen transported to the tissues to decrease ordinarily increases the rate of red blood cell production. </li></ul><ul><li>Thus, when a person becomes extremely anemic as a result of hemorrhage or any other condition, the bone marrow immediately begins to produce large quantities of red blood cells. </li></ul><ul><li>Also, destruction of major portions of the bone marrow by any means, especially by x-ray therapy, causes hyperplasia of the remaining bone marrow, thereby attempting to supply the demand for red blood cells in the body. </li></ul>
  73. 73. High Altitudes <ul><li>At very high altitudes, where the quantity of oxygen in the air is greatly decreased, insufficient oxygen is transported to the tissues, and red cell production is greatly increased. </li></ul><ul><li>In this case, it is not the concentration of red blood cells in the blood that controls red cell production but the amount of oxygen transported to the tissues in relation to tissue demand for oxygen. </li></ul>
  74. 74. Diseases <ul><li>Various diseases of the circulation that cause decreased blood flow through the peripheral vessels, and particularly those that cause failure of oxygen absorption by the blood as it passes through the lungs, can also increase the rate of red cell production. </li></ul><ul><li>This is especially apparent in prolonged cardiac failure and in many lung diseases, because the tissue hypoxia resulting from these conditions increases red cell production, with a resultant increase in hematocrit and usually total blood volume as well. </li></ul>
  75. 75. <ul><li>Erythropoietin </li></ul>
  76. 76. <ul><li>A hormone called erythropoietin and low oxygen levels regulate the production of RBCs. </li></ul><ul><li>Any factor that decreases the oxygen level in the body, such as lung disease or anemia (low number of RBCs), increases the level of erythropoietin in the body. </li></ul><ul><li>Erythropoietin then stimulates production of RBCs by stimulating the stem cells to produce more RBCs and increasing how quickly they mature. </li></ul><ul><li>Ninety percent of erythropoietin is made in the kidneys . When both kidneys are removed, or when kidney failure is present, that person becomes anemic due to lack of erythropoietin. </li></ul><ul><li>Iron, vitamin B-12 and folate are essential in the production of RBCs. </li></ul>Dr Alamzeb MBB M.Phil
  77. 77. Hypoxia Erythropoietin RBCs production factors that decrease tissue oxygenation 1 Low blood volume 2 anemia 3 low hemoglobin 4 poor blood flow 5 pulmonary disease 6 cardiac disease 8 hemorrhage Decrease Tssue oxygenation Increase Erythropoietin kidney Hemopoietic stem cells Proerythroblasts Red blood cells Dr Alamzeb MBB M.Phil
  78. 78.
  79. 79. ROLE OF VITAMIN B12 AND FLIC ACID IN MATURATION OF RBCs <ul><li>B12 & folic acid is important for final maturation of RBCs. </li></ul><ul><li>Both of these are essential for the synthesis DNA </li></ul><ul><li>Because each in a different way is required for the formation of thymidine triphosphate,one of the essential building block of DNA. </li></ul><ul><li>There fore lack of either B12 or folic acid cause abnormal & diminished DNA & consequently, failure of nuclear maturation & cell division. </li></ul><ul><li>Furthermore the erythroblast fails to proliferate rapidly & produce large red cells called Macrocytes, has a flimsy & often irregular membrane </li></ul><ul><li>the oxygen carrying capacity is normal but the life span is reduced by one half to one third normal. </li></ul>
  80. 80. Hemoglobine break down Dr Alamzeb MBBS M.Phil
  81. 81. S U M M E R Y Alamzeb MBBS M.Phil
  82. 82. Functions of RBCs Dr Alamzeb MBBS M.Phil
  83. 83. <ul><li>The primary function of red blood cells is to transport oxygen from the lungs to all cells of the body. </li></ul><ul><li>RBCs contain a protein called hemoglobin that actually carries the oxygen. </li></ul><ul><li>In the capillaries, the oxygen is released to be used by the cells of the body. </li></ul><ul><li>Ninety-seven percent of the oxygen that is carried by the blood from the lungs is carried by hemoglobin; the other three percent is dissolved in the plasma. </li></ul><ul><li>Hemoglobin allows the blood to transport 30 to 100 times more oxygen than could be dissolved in the plasma </li></ul><ul><ul><ul><ul><ul><li>Alamzeb MBBS M.Phil </li></ul></ul></ul></ul></ul>
  84. 84. <ul><li>Hemoglobin combines loosely with oxygen in the lungs, where the oxygen level is high, and then easily releases it in the capillaries, where the oxygen level is low. </li></ul><ul><li>Each molecule of hemoglobin contains four iron atoms, </li></ul><ul><li>and each iron atom can bind with one molecule of oxygen (which contains two oxygen atoms, called O 2 ) </li></ul><ul><li>for a total of four oxygen molecules (4 *O 2 ) or eight atoms of oxygen for each molecule of hemoglobin. </li></ul><ul><li>The iron in hemoglobin gives blood its red color. </li></ul>
  85. 85. <ul><li>Carbon dioxide is formed in the cells as a byproduct of many chemical reactions. </li></ul><ul><li>It enters the blood in the capillaries and is brought back to the lungs and released there and then exhaled as we breathe. </li></ul><ul><li>RBCs contain an enzyme called carbonic anhydrase which helps the reaction of carbon dioxide (CO 2 ) and water (H 2 O) to occur 5,000 times faster. </li></ul><ul><li>Carbonic acid is formed, which then separates into hydrogen ions and bicarbonate ions: </li></ul>
  86. 86. Chemical reaction CO2 + H2O H2CO3 H + + HCO 3- Carbonic Anhydrase carbon dioxide + water carbonic acid + hydrogen ion + bicarbonate ion Alamzeb MBBS M.Phil
  87. 87. <ul><li>The hydrogen ions then combine with hemoglobin </li></ul><ul><li>and the bicarbonate ions go into the plasma. </li></ul><ul><li>Seventy percent of the CO 2 is removed in this way. </li></ul><ul><li>Seven percent of the CO 2 is dissolved in the plasma. </li></ul><ul><li>The remaining 23 percent of the CO 2 combines directly with hemoglobin and then is released into the lungs. </li></ul>Alamzeb MBBS M.Phil
  88. 88. OTHER FUNCTIONS BESIDES TRANSPORT OF HEMOGLOBIN. <ul><li>The red blood cells contain a large quantity of carbonic anhydrase, an enzyme that catalyzes the reversible reaction between carbon dioxide (CO 2 ) and water to form carbonic acid (H 2 CO 3 ), increasing the rate of this reaction several thousand fold.H2o+Co2 H2Co3 </li></ul><ul><li>The rapidity of this reaction makes it possible for the water of the blood to transport enormous quantities of CO 2 in the form of bicarbonate ion (HCO 3 - ) from the tissues to the lungs, </li></ul><ul><li>where it is reconverted to CO 2 and expelled into the atmosphere as a body waste product. </li></ul><ul><li>The hemoglobin in the cells is an excellent acid-base buffer (as is true of most proteins), so that the red blood cells are responsible for most of the acid-base buffering power of whole blood. </li></ul>