Mini Course 6 Body Fluids 2024 PDF

1. BLOOD  OBJECTIVES  Name the components of blood  Name the components of a haemoglobin molecule  Discuss the factors responsible for anaemia  Describe the transportation of oxygen and carbon dioxide in the blood and their interchange in the tissues  Discuss the role of various coagu...

1. BLOOD  OBJECTIVES  Name the components of blood  Name the components of a haemoglobin molecule  Discuss the factors responsible for anaemia  Describe the transportation of oxygen and carbon dioxide in the blood and their interchange in the tissues  Discuss the role of various coagulation factors in the blood  List the composition of blood buffers and discuss how they maintain blood pH BLOOD COMPOSITION Plasma Water (91.5%) Proteins (7%) (55%) Other solutes (1.5%) Platelets Suspending (150 000-400 000) particles White blood cells (45%) (5 000-10 000) Red blood cells (4.8 – 5.4 million) Number of cells per µl blood 91.5% of plasma is H2O 8.5% solids dissolved or colloidally dispersed in blood Most important of all plasma solids are the blood/plasma proteins (7.5%) Serum Albumin Globulins Fibrinogen Other solutes (1.5%) Nutrients Gases Inorganic salts Waste products Enzymes Vitamins Hormones & Antibodies  Main constituent is haemoglobin  Lack nucleus and most organelles  Polycythaemia  Excess of red blood cells  Anaemia  Shortage of red blood cells  Erythropoietin  Hormone that stimulates red blood cell formation  Formed by the action of a substance produced in the kidneys (renal erythropoietic factor)  If the kidney don’t function properly → anaemia  WBC larger than red blood cells  WBC have a nucleus red blood cells do not  Several types of WBC  Basophils  Eosinophils  Lymphocytes  Monocytes  Neutrophils  WBC attack & destroy harmful microorganism – defence against infection  WBC count above normal usually indicates infection This Photo by Unknown Author is licensed under CC BY   Platelets are smaller than RBC  Platelets do not have an nucleus  Contain cephalin which is a phospholipid that is involve in blood clotting This Photo by Unknown Author is licensed under CC BY  On standing freshly drawn blood clots  When the clot settles yellowish liquid remains =  blood serum  Blood serum is blood without blood cells and without fibrinogen  To keep blood from clotting an anticoagulant must be added GENERAL PROPERTIES OF BLOOD  Density of whole blood – 1.054-1.060g/l  Blood Viscous  Blood slightly alkaline (pH range 7.35-7.45)  Acidosis  pH of blood falls slightly below 7.35  Alkalosis  pH of blood rises slightly above 7.45 Blood analysis  For Lab tests 5ml of blood collected from a vein in the arm before breakfast  Whole blood  Blood plasma  Blood serum BLOOD VOLUME  8-9% of total body weight is blood  Volume is ±5-7L in an adult  Blood Volume increases during pregnancy  Blood Volume decreases during diarrhoea & haemorrhaging  Blood Volume can be rapidly replaced  EFFECT OF MEALS AND POSITION ON CONCENTRATIONS OF BLOOD SUBSTANCES  Blood samples are usually taken after a period of fasting (8-12 hours)  Fasting – other than water no foodstuff taken  Position also affect concentration of blood substances  Person who has been resting horizontally for several hours will have a 12-15% greater blood volume than a person who is standing  Greater blood volume → decreased concentration of blood substances  Results from a person sitting intermediate between those standing and those lying down  OBJECTIVES  Name the components of blood  Name the components of a haemoglobin molecule  Discuss the factors responsible for anaemia  Describe the transportation of oxygen and carbon dioxide in the blood and their interchange in the tissues  Discuss the role of various coagulation factors in the blood  List the composition of blood buffers and discuss how they maintain blood pH  HAEMOGLOBIN  What is haemoglobin?  Red pigment present in RBC which transport O2 to the tissues  Conjugated Protein  Protein part → globin  Iron containing part → haem  Haemoglobin synthesize in the bone marrow  Synthesis of haemoglobin depends on:  Iron  Folic acid  Vitamin B12  Amino acids (Deficiency of any of these factors decrease the ability of bone marrow to synthesize haemoglobin)  One haemoglobin molecule have 4 polypeptide chain and 4 haem molecules  Each haem molecule is located in a pocket formed by the folding of the polypeptide chain  Haem part consist of a porphyrin ring with one iron (Fe2+) at the center  Oxygen bind to the Fe2+ atoms of the haem  CO2 bind to the α-amino group of the N-terminal end of the polypeptide chain  HAEMOGLOBIN (HB)  Normal adult blood consists of 2 types of Hb  HbA1 – 97% of total Hb  HbA2 – 3% of total Hb  Foetus and new-born baby contains another type of Hb called foetal haemoglobin (HbF)  HbF binds O2 more tightly than adult haemoglobin  Foetus can draw oxygen from mothers blood  Foetal haemoglobin transforms to normal haemoglobin soon after birth  MYOGLOBIN  Myoglobin globular protein similar to haemoglobin (contains haem group)  Haemoglobin involve in transportation of O2 to the tissues  Myoglobin stores O2 in red muscle tissues such as heart muscle  Myoglobin binds O2 more strongly than haemoglobin  Myoglobin is a monomeric protein  Under conditions of oxygen deprivation myoglobin releases O2 to the heart muscle for the synthesis of ATP  OBJECTIVES  Name the components of blood  Name the components of a haemoglobin molecule  Discuss the factors responsible for anaemia  Describe the transportation of oxygen and carbon dioxide in the blood and their interchange in the tissues  Discuss the role of various coagulation factors in the blood  List the composition of blood buffers and discuss how they maintain blood pH  WHAT IS ANAEMIA?  When RBC/haemoglobin content of blood falls below normal  Anaemia can result from:  Decreased rate of RBC production  Increased destruction of RBC  Increased loss of RBC   A decreased rate of production of RBC may be due to various diseases that destroy/suppress the activity of blood- forming tissues  E.g leukaemia, multiple myeloma & Hodgkin’s disease  Radiation, drugs such as benzene and WHAT CAN gold salts also decrease activity of blood-forming tissues CAUSE  Diet lacking in iron and protein also decrease RBC production ANAEMIA?  A decrease in RBC production may also be caused by poisons and infections that cause haemolysis  CO poisonous gas because haemoglobin combines with it faster than it does with O2 (carboxyhaemoglobin is very stable – only small amount of haemoglobin left to carry O2  OBJECTIVES  Name the components of blood  Name the components of a haemoglobin molecule  Discuss the factors responsible for anaemia  Describe the transportation of oxygen and carbon dioxide in the blood and their interchange in the tissues  Discuss the role of various coagulation factors in the blood  List the composition of blood buffers and discuss how they maintain blood pH   O2 carried from lungs to the tissue by haemoglobin in blood  CO2 carried from tissues to the lungs by haemoglobin in blood TRANSPORTATION NB!! Gases always diffuse OF OXYGEN AND from an area of high concentration to one of CARBON DIOXIDE lower concentration IN THE BLOOD  Inspired air has a higher concentration of O2 than blood in the alveoli of the lungs  Cells have a higher concentration of CO2 than the blood  OXYGEN  Oxygen binds to the Fe2+ atoms of the haem portion of the haemoglobin (HHb) molecule to form oxyhaemoglobin (HbO2-).  Each haemoglobin molecule has four haem group thus each haemoglobin molecule can bind a total of four O2 molecules  When oxygen enters the lung the oxygen pressure is high - all Fe2+ ions in haemoglobin saturated with O2 molecules HHb + O2 HbO2- + H+  Oxygen carried from the lungs to the tissues as oxyhaemoglobin  In the tissue the oxygen pressure is low oxygen flows from arterial blood to tissues HbO2- + H+ O2 + HHb This Photo by Unknown Author is licensed under CC BY-SA-NC  The release of oxygen in the tissues favour the deoxygenated form of haemoglobin  This Photo by Unknown Author is licensed under CC BY CARBON DIOXIDE This Photo by Unknown Author is licensed under CC BY  CARBON DIOXIDE 1. Bound to the α-amino group of the N-terminal end of each polypeptide chain of the haemoglobin molecule to form carbaminohaemoglobin Each haemoglobin molecule can carry a maximum of four CO2 molecules HHb + CO2 HHbCO2 2. Carried in the plasma as H2CO3  CO2 produced in cells diffuses from tissues into the bloodstream  In the red blood cells it reacts with water in the cell to form carbonic acid  The reaction is catalyse by the enzyme carbonic anhydrase Carbonic anhydrase CO2 + H2O H2CO3  Carbonic acid dissociates to yield hydrogen and bicarbonate ions H2CO3 H+ + HCO3- 3. Carried as dissolved gas LUNGS TISSUES/ CELLS O2 O2 + HHb → HbO2- + H+ HbO2- + H+ HHb + O2 H2CO3 H+ + HCO3- HCO3- + H+ CO2 H2O+ CO2 H2CO3 H2O + CO2 CO2 CO2 HHbCO2 HHbCO2 HHb + CO2 TISSUES/ LUNGS CELLS  OBJECTIVES  Name the components of blood  Name the components of a haemoglobin molecule  Discuss the factors responsible for anaemia  Describe the transportation of oxygen and carbon dioxide in the blood and their interchange in the tissues  Discuss the role of various coagulation factors in the blood  List the composition of blood buffers and discuss how they maintain blood pH  PLASMA PROTEINS  Constitute ±7% of plasma  Usually divided into 3 groups  Albumin  Fibrinogen  Globulins  α - Globulin  β – Globulin  γ - Globulin Nayak Page 42  ALBUMIN  Osmotic Function  Maintain blood volume & body fluid distribution the body  Decreased in plasma albumin levels decrease in osmotic pressure  Increased fluid retention in tissue spaces = oedema  Transport function  Transport of hydrophobic substances  E.g. free fatty acids, steroid hormones, calcium  Nutritive Function  When broken down source of amino acids  Buffering Function  All proteins have buffering capacity Nayak Page 43  GLOBULINS  Subdivided into:  α , β & ᵞ-globulins  α , β – Globulins transport proteins:  Carbohydrates – (mucoprotein & glucoprotein)  Lipids – (lipoprotein)  Metal ions- ( transferrin for iron)  ᵞ-globulins – immunoglobins  Protect body against infections Nayak Page 43 FIBRINOGEN  Plasma protein involve in clotting of blood  Manufactured in the liver  Any disease that destroys liver tissue causes a decrease in amount of fibrinogen Nayak Page 43   Rupturing of skin leads to blood flowing out & a clot soon form  When blood is taken from a vein and placed in a test tube it soon forms a clot BLOOD Why does blood clot when it is CLOTTING removed from its normal place in the circulating system? Why doesn’t blood clot in the blood vessels ?  BLOOD CLOTTING  When blood clots a series of reactions occur  the soluble plasma protein fibrinogen is converted into insoluble fibrin  Fibrin precipitates to form a spongy mass which traps and holds the blood cells BLOOD CLOTTING  When a blood vessel is cut, the blood comes in contact with the exposed tissue  This contact activates 2 separate systems of coagulation  The Intrinsic system - All components needed to form a clot found in blood  The Extrinsic system - Need components released from other tissue STOPPAGE OF BLEEDING/HAEMOSTASIS BLOOD VESSEL INJURY Exposed collagen Vasoconstriction Activation of coagulation Platelet reaction and Aggregation Thrombin Temporary plug FIBRIN PLUG THREE MECHANISMS OF HAEMOSTASIS (STOPPAGE OF BLEEDING OR BLOOD FLOW) 1. Vasoconstriction  At the site of injury –reducing the blood flow 2. Platelet aggregation  Form temporary plug in the injured capillaries  Prostaglandins and thromboxanes are required for this action  Since aspirin interferes with the action of prostaglandins, it also interferes with the clotting process 3. Fibrin clot  Calcium ions are necessary for the clotting of blood  A deficiency of vitamin K reduces the production of prothrombin without which blood cannot clot  Anticoagulant drugs reduce the conversion of prothrombin to thrombin and so keep blood from clotting rapidly  Heparin speeds up the removal of thrombin  OBJECTIVES  Name the components of blood  Name the components of a haemoglobin molecule  Discuss the factors responsible for anaemia  Describe the transportation of oxygen and carbon dioxide in the blood and their interchange in the tissues  Discuss the role of various coagulation factors in the blood  List the composition of blood buffers and discuss how they maintain blood pH  ACID-BASE BALANCE  Normal pH range of blood is 7.35-7.45  Acidosis – pH below 7.35  Alkalosis – pH raises above 7.45  Acidosis more common than alkalosis because many of metabolic products produced = acidic How does the blood maintain the pH when acidic and basic substances are continuously being added to it?  The presence of buffers present in blood plasma and RBC  Buffers are substances that resist a change in pH (usually a weak acid & a salt of a weak acid) Nayak Page 206 BLOOD BUFFERS Carbonate-Bicarbonate buffer HCO3-/H2CO3 Phosphate buffers HPO4/H2PO4 Protein buffers Haemoglobin & Oxyhaemoglobin Albumin  RBC – Carbonic acid (H2CO3) and Potassium bicarbonate (KHCO3)  Plasma – Carbonic acid (H2CO3) and Sodium bicarbonate (NaHCO3)  Metabolic acid added to blood  React with basic component of buffer system  Produce salt and weak acid  Weak acid decompose to CO2 and H2O  Stimulation of respiration to eliminate CO2  Metabolic base added to blood  React with acid component of buffer system  Produce salt of a weak acid + water  H2C03 concentration decreases because it reacts with base  More CO2 needed to combine with H2O to form H2C03  Respiration decreases Nayak Page 206  Metabolic acid added to blood  React with basic component of buffer system  Produce salt and weak acid  Weak acid decompose to CO2 and H2O  Stimulation of respiration to eliminate CO2 NaHCO3 + HCl NaCl + H2CO3 H2CO3 H2O + CO2 Nayak Page 206  Metabolic base added to blood  React with acid component of buffer system  Produce salt of a weak acid + water  H2C03 concentration decreases because it reacts with base  More CO2 needed to combine with H2O to form H2C03  Respiration decreases H2CO3 + NaOH NaHCO3 + H2O CO2 + H2O H2CO3 Nayak Page 206 PHOSPHATE BUFFERS  Main intracellular buffer  Na2HPO4 and NaH2PO4  Function similarly to the bicarbonate buffers in neutralizing excess acid and base  Account for more then half of the total buffering action of blood  Haemoglobin and albumin play important role as protein buffers in bloodstream  Why can proteins act as buffers?  FUNCTION OF THE KIDNEYS IN ACID-BASE BALANCE  Maintain acid-base balance by:  Excreting either acidic/basic urine  pH range 4.5-9.5  Reabsorption, secretion or excreting of non-volatile acids  E.g. lactic acid, pyruvic acid etc..  Conserve fixed bases through production of NH3  Acid substances in blood combine with ammonia and are excreted as ammonium salts- this saves sodium and potassium ions  Acidosis  pH falls below 7.35  Causes include uncontrolled diabetes with ketosis, severe exercise, renal failure, poisoning with acid, severe diarrhoea, severe dehydration  Alkalosis  pH of blood rises above 7.45  Causes include prolonged vomiting, gastric suction, renal disease, massive blood transfusions, diuretic therapy  FLUID ELECTROLYTE BALANCE  Normally water intake balance by water output  Oedema – intake exceeds output  Dehydration – output exceeds intake  Water Balance  The body replenishes its water supply in 3 ways:  Ingestion of liquids  Ingestion of foods  By metabolic processes taking place normally in the body  Body loses water in several ways  Through the kidneys (urine)  Through the skin (perspiration)  Through the lungs (exhaled moisture)  Through the faeces FLUID ELECTROLYTE BALANCE  Distribution of water in the body  Two major areas  Intracellular (55%)  Extracellular (45%)  Electrolyte Balance  Ions are divided into 2 groups  Cations (Positively charge ions)  Na+, K+ Mg2+, Ca2+  Anions (Negatively charge ions)  Cl-, HCO3-, PO4 3- ,etc.  Principal cation in intracellular fluid = potassium  Principal cation in the extracellular fluid = sodium CLINICAL IMPORTANCE OF MINERAL CATIONS AND ANIONS  Mineral required for the body can be divided into 2 main groups:  Macrominerals  Required in amounts greater than 100mg per day  Sodium ions, Potassium ions, Calcium ions, Magnesium ions, Chloride ions & Phosphate ions  Microminerals (Trace Elements)  Required in amounts less than 100mg per day  Iron ions, Copper ions, Zinc ions, etc 2. Urine Recall the properties and functions of the body’s fluids  List the organic, inorganic and abnormal constituents of urine Explain the meaning of: Proteinuria Glucosuria Haematuria Oliguria Anuria Polyuria  Waste products of the body excreted through the: Lungs eliminate H2O and CO2 through expired air Skin Perspiration (H2O small amount of inorganic and organic salts) Intestines Feces (undigested + undigestible material + excretory products from the liver, H2O & some inorganic and organic salts) Liver bile, pigments & cholesterol Kidneys Primarily excreting organ of the body Excrete water and water-soluble compounds Also important for role in control and regulation of water, electrolyte and acid-base balance in the body  Urine Formation Regulation of Fluid and Electrolyte balance Regulation of Acid-Base balance Hormonal function Excretion of nonprotein nitrogenous (NPN) substances Blood flows into kidney Remaining liquid (urea + waste products) flows to the collecting tubules and then to the bladder  The kidneys act as very efficient filters Approximately 1 L of blood is filtered through kidneys/min The kidneys remove waste products but not the needed nutrients in the blood Urine carries waste products and excess water out of the body Normal adult excretes 750-2500 ml urine per day with the average of about 1500 ml/day Depends on liquid intake & weather conditions Drugs (eg. Caffeine) and alcohol diuretic effect  Volume pH Colour Odour Specific gravity  List the organic, inorganic and abnormal constituents of urine Explain the meaning of: Proteinuria Glucosuria Haematuria Oliguria Anuria Polyuria  Normal adult excretes 750-2500 ml urine per day with the average of about 1500 ml/day Polyuria Excessive production of urine. Pathologic conditions or excessive liquid intake Oliguria Decreased flow of urine. Daily urinary output of less than 250 ml. Eg. during fever Anuria Total lack of urine excretion or daily urine output of less than 50 ml. Indicates extensive kidney damage  Normally slightly acidic pH varies to compensate for diet and products of metabolism pH range (4.5-8)  Normal colour pale yellow to amber Pigment urochrome – derivative of urobilin produce from bilirubin degradation Colour intensity correlates with the concentration of the urine Colour varies with amount of urine produced & concentration of solutes in urine Colourless – reduced concentration Brownish yellow – Obstructive jaundice Reddish brown – Blood (haemoglobin) Bright yellow – Vitamin B Freshly voided urine clear Develop sediment after standing for a while because of precipitation of calcium phosphate  Distinctive odour Aromatic odour – Normal urine due to aromatic acids Ammonia odour – On standing due to decomposition of urea In some pathological conditions certain metabolites my produce specific odour Fruity odour – Diabetes due to the presence of ketones Offensive odour – Bacterial infection Diet can also modify odour of urine  Specific gravity measure the amount of substances dissolved in urine The greater the concentration of solutes the greater the density Specific gravity is a measure of the kidney’s ability to concentrate urine If kidneys make urine with a high amount of water - urine a low specific gravity Diabetes mellitus Density greater due to high concentration of sugar in urine Diabetes insipidus Density low due to large amounts of H2O being secreted  Urine complex fluid composed of 95% H2O and 5% solids Urine contain end products of metabolism carried out by the cells in the body Almost all substances in urine also in blood - (different concentrations)  Urine 5% Dissolved 95% H2O solids 2.5% (half) 2.5% Other Urea solids Inorganic Organic Creatine Cl-, Na+, K+ Uric acid  List the organic, inorganic and abnormal constituents of urine Explain the meaning of: Proteinuria Glucosuria Haematuria Oliguria Anuria Polyuria  Urea End product of protein metabolism Uric Acid Product of metabolism of purines from nucleoproteins Increased output in leukaemia, severe liver disease, various stages of gout Deposits of uric acid in joints characteristic of gout Under certain conditions , crystallize in the kidneys = kidney stones Creatine Produced in the body from three amino acids (arginine, methionine & glycine) Usually present in muscle, brain and blood Creatinuria Abnormal amounts of creatine in the urine May occur during starvation, diabetes mellitus & prolonged fevers Creatinine Product of the breakdown of creatine Also small amounts of vitamins, other hormones & enzymes  List the organic, inorganic and abnormal constituents of urine Explain the meaning of: Proteinuria Glucosuria Haematuria Oliguria Anuria Polyuria  Chloride ions Varies with intake of NaCl Excretion decreased in fevers Sodium ions Varies with intake and body’s requirements Phosphates Depends on diet Increased when diet contains food high in phosphorus Sulphates Derived from the metabolism of sulphur containing proteins Influenced by diet Ammonium Ions Derived from the hydrolysis of urea Other Ions Calcium, magnesium & potassium  List the organic, inorganic and abnormal constituents of urine Explain the meaning of: Proteinuria Glucosuria Haematuria Oliguria Anuria Polyuria  Protein Urine should not normally contain protein Proteinuria- presence of protein in urine (kidney disease) Test for proteins in urine based on the fact that protein coagulates when heated Glucose Glucosuria – presence of glucose in urine Test with Benedict’s reagent May be found in urine after heavy muscular exercise, a meal high in carbohydrates, diabetes mellitus or liver damage Other sugars Lactose & galactose during pregnancy and lactation  Ketone Bodies During diabetes mellitus, starvation or inadequate carbohydrate intake Kidneys produce more ammonia to neutralize the ketone bodies Blood Haematuria- presence of blood in the urine Result from lesions or stones in the kidneys/ urinary tract Haemoglobinuria presence of haemoglobin in the urine Result from haemolysis of RBC caused by injection of hypotonic solution, severe burns, or blackwater fever Phenylpyruvic acid Intermediate product in metabolism of the essential amino acid phenylalanine Present in the urine of a person with Phenylketonuria  Bile Indicates obstruction of flow to the intestines Bilirubin Bile pigments not normally present in urine Present in patients with conjugated hyperbilirubinemia Urobilinogen Indicative of haemolytic jaundice Creatine Normally small amounts of creatine present in urine Elevated levels indicative of muscle wasting disease Uric Acid Elevated levels can indicate gout