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IntroductionPhysiology is the study of the
living things.(from Greek physis nature
logos study physiology is concerned with the
way the human body works. It is the study of the
functions of systems and organs. Organs consist
of tissues which are formed of cells
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Blood

• A vital fluid which circulates within
  cardiovascular system.
• The total blood volume is about 5600ml in a 70 kg
  man( 8 of body weight).
• It is composed of two main parts
• -plasma 55
• -cellular elements 45.....RBCs, WBCs
  and platelets

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• Blood

45 blood elements Erythrocytes Leucocytes Plate
lets
55 Plasma - Water - Inorganic
substances Na, cl -Organic
substances plasma proteins plasma
lipids glucose amino acids
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• Function of the blood
• Transport function
• e.g. glucose, oxygen, carbon dioxide,
  hormones,.
• Defensive function
• e.g. white blood cells
• Hemostatic function
• stoppage of bleeding after injury
• Homeostatic function
• whats homeostasis?

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Homeostasis maintenance of constant conditions
in the internal environment
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Site of hematopoiesis.. in fetus --------Liver
spleen in adult ------- Bone marrow
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Plasma

• It is a yellow clear fluid composed of
• Water 90
• Inorganic substances 0.9 Na , Cl- , HCO3
• Organic substances 9.1
  
• -plasma proteins
• -lipidstriglycerides, cholesterol
  fatty acids
• -other organic substances glucose,
  amino acids, vitamins, enzymes, waste products
• 4 Blood gases O2 , CO2 .

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• Plasma Proteins
• albumin
• globulins (a, ß ?)
• prothrombin
• fibrinogen
• -Concentration 7 gm \dl
• -Site of formation..?
• .liver ( albumin, fibrinogen,prothrombin
  50 of globulins)
• .lymphocytes (gamma globulin)
• -albumin/globulin ratio ??

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• Albumin-globulin ratio ( A/G Ratio)
• Normal A/G ratio 1.2 1.6
• It is decreased in
• 1- liver diseases decreased albumin
  production
• 2- renal diseases..albumin is lost in urine

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• Functions of plasma proteins
• Osmotic function.albumin ( oncotic pressure)
• Defensive function. ? globulins
• Blood clotting..prothrombin and fibrinogen
• Blood viscosity. fibrinogen
• Buffer function
• Capillary function
• transport function( hormones, metals, drugs..)

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Red Blood CorpusclesErythrocytes / RBCs

• Biconcave discs
• count . 4.5 - 5.5 million /mm3
• structure
• -semipermeable membrane
• -hemoglobin ( content and function)
• -no nucleus
• Life span .. 120 days

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• Hemoglobin( Hb)
• Hem..iron containing porphyrin derivatives
• Globinprotein part formed of 4 polypeptide
  chains
• Hb A ..2 a 2 ß (96- 98 of Hb in adult)
• Hb A2 .2 a 2 d ( 2.5 of adult Hb)
• Hb F .2 a 2 ? ( Hb of fetus-more
  affinity to O2 )
• Function of Hb
• 1- transport oxygen from lungs to tissues
  carbon dioxide from tissues to the lungs
• 2- buffering action

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• Erythropoiesis
• Definitionformation of new RBCs
• Site
• in fetus -------- Liver spleen
• in adult ------- Bone marrow

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Factors affecting erythropoiesis

• Oxygen supply to the tissues
• decreased oxygen.erythropoietin.increased RBC
• (erythropoietin hormone ? )
• 2. Healthy bone marrow (erythropoiesis in adult)
• 3- healthy liver ( why ? )
• storage of Fe, Vit B12, erythropoiesis in
  fetus
• 4. Dietiron, vitaminC, vitamin B12 and folic
  acid
• - iron.hemoglobin formation
• - Vit B12 folic acidDNA synthesis cell
  division
• - proteins..globin formation
• 5. Hormones
• androgen, thyroid glucocorticoid
  hormones stimulates
  erythropoiesis

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Erythropoietin

• Glycoprotein hormone
• Hypoxia is the main stimulus for its secretion
• In adult 85 is formed by the kidney and 15 is
  formed by the liver
• It Stimulates all steps of erythropoiesis and
  increases the production of RBCs

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Hypoxia, cobalt salts, androgens (testosterone),
catecholamines, corticosteroids, growth hormone,
and thyroxin.

• production of proerythroblast from the stem
  cells.
• Increasing the speed of conversion of one step to
  the other in the erythroblastic stages.
• It accelerates the synthesis of Hb.

Erythropoietin
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• Iron
• Gastric HCl vitamin C reduce iron from ferric
  state to ferrous state
• Iron is absorbed in upper small intestine
• Iron is found in Hb, myoglobin ferritin (
  storage frorm)
• Folic acid
• Essential for DNA synthesis cell division
• Vitamin B12
• Essential for DNA synthesis, cell division
  metabolism of myelin sheath
• It unites with intrinsic factor from the stomach
  then absorbed from terminal ileum
• Deficiency-----macrocytic anemia neurological
  symptoms
• Treatment by injection of vit B12

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• Anemia
• It is a decrease in number of RBCs, hemoglobin
  content or both.
• normal RBCs count.4.5 - 5.5 million/
  mm3
• normal Hb content...13.5 15.5 gm/ dl
• Types
• 1- normocytic normochromic anemia
• hemorrhage, hemolytic anemia bone marrow
  depression (aplastic
• anemia)
• 2-microcytic hypochromic anemia
• iron deficiency( decreased iron intake
  absorption chronic blood loss)
• 3- macrocytic hyperchromic anemia
• vit B112 deficiency absent intrinsic
  factor, disease of lower ileum, decreased storage
  in liver disease
• folic acid deficiency decreased intake,
  disease of small intestine ,cytotoxic drugs

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• Pernicious anemia
• autoimmune disease of elderly women
• Macrocytic anemia and nervous manifestations
• caused by absence of HCL intrinsic factor
• Polycythemia
• Increased number of RBCs
• Primary polycythemia ( Polycythemia Vera)
• Increased RBCs, WBCs platelets
• Secondary polycythemia
• Increased RBCs in hypoxia