1. Blood

2. Blood The liquid form of connective tissue in which cells are suspended in a circulating fluid, the plasma About 5.5 L in humans

3. Composition of blood Liquid Intercellular substance (Plasma) 50-60% of actual blood volume Homogenous, slightly alkaline fluid which contains: Organic substances Inorganic substances Enzymes Hormones Solid or formed elements 40-50% of actual blood volume Cellular elements RBC/erythrocytes WBC/leukocytes Platelets/thrombocytes Non-cellular elements Hemoconia – blood dusts Chylomicrons or tiny fat droplets

4. Serum Clear yellow liquid of clotted blood When circulation ceases, or when blood is exposed to air, one of the globulins of plasma (fibrinogen) precipitates as a network of fine filaments, the fibrin. The contraction of clotted blood or plasma (syneresis) expresses a clear yellow fluid called SERUM

5. Composition of Plasma Plasma is an aqueous solution containing substances of low or high molecular weight that make up 10% of its volume Plasma proteins – 7% Albumin – alpha and beta Gamma globulins Lipoproteins Proteins that precipitate in blood coagulation (prothrombin and fibrinogen) Inorganic salts – 0.9% Organic compounds – amino acids, vitamins, hormones, lipoproteins – of various origins

6. Hematocrit Is an estimate of the volume of packed erythrocytes per unit volume of blood Normal value: Adult male – 40-50% Adult female – 35-45% and diminishes by physiologic hemodilution during pregnancy Children up to 10 – 35% Newborn – 45-60%

7. Cellular Elements of blood

8. RBC or Erythrocytes Anucleate (no nucleus) Packed with the oxygen-carrying protein, HEMOGLOBIN (heme-iron portion;globin-protein portion) Small 7.5 μm in diameter Biconcave in profile Non-granular Non-motile Acidophilic staining cells

9. RBC or Erythrocytes “dumbbell” in shape - in profile osmotic pressure of vacuum of blood vessels sucks RBC membrane causing constriction at the middle provides the erythrocytes a large surface-to-volume ratio, thus facilitating gas exchange Elastic – suffers changes in shape when passing into environmental obstacles Cytoplasm – homogenous and non-granular Fresh cytoplasm – yellowish green Cytoplasm when stained – red, orange, pink due to acid stain

10. RBC or Erythrocytes Acidophilic staining property is due to hemoglobin (14-16 grams/100 cc of blood) Lifespan – 10 to 120 days (during its life = 700 miles of travel) Normal RBC count 4.5 M/cu mm of blood Female – 3.9 to 5.5 M/cu mm of blood Male – 4.1 to 6 M/cu mm of blood

11. Terminologies

12. Anemia Decreased concentration of red blood cells in the circulating blood It is also possible for the number of red blood cells to be normal but for each cell to contain a reduced amount of hemoglobin May be caused by: Loss of blood (hemorrhage) Insufficient production of red blood cells by the bone marrow Production of RBC with insufficient hemoglobin – related to iron deficiency anemia Accelerated blood cell destruction

13. Polycythemia or Erythrocytosis Increase in RBC count Physiologic adaptation – found in people living in high altitudes where oxygen tension is low

14. Special Features/Behavior of Red Blood Cells

15. Rouleaux formation RBC adhere themselves to one another due to surface tension Appear as “columns” or “piles of coins”

16. Crenation RBC’s spiked shrunk appearance Induced in vitro by: exposure to fatty acids, lysolecithin, anionic compunds or elevated pH Erythrocytes assume a spiny configuration with 10 – 30 spicules regularly distributed over their surface and are thus called echinocytes

17. Behavior of RBC when exposed to solutions of different concentrations Hypertonic solution Hypotonic solution Solution of greater concentration gradient Flow of water: from low to high RBC shrinks Isotonic solution Equal concentration, equal pressure (0.9% NaCl) No change Solution of lesser concentration and less osmotic pressure causing swelling of RBC Water goes to cell causing the cell to swell and eventually burst and disintegrate

18. Anisocytosis – variation in RBC size Macrocyte – large RBC (9 μm) Normocyte – normal RBC (7 – 8 μm) Microcyte – small RBC (6 μm) Poikilocytosis – variation in RBC shape Ovalocytes Spherocytes - inelastic Sickle cells – “crescent-like”, sickling, inelastic, with abnormal hemoglobin, hereditary factors (etiology) Target cells – abnormally shaped RBC in some cases of anemia; do not undergo roleaux formation

19. Anisochromia – variation in RBC color Hyperchromic – more color, more hemoglobin Normochromic – normal color, normal hemoglobin Hypochromic – less color, less hemoglobin Agglutination - sludging Clumping of RBC due to agglutinin (anti-bodies) Happens in unmatched blood

20. RBC particles Heinz bodies Granules found in normal RBC Due to congenital suseptibility to drugs Howell-Jolly bodies Remnants of nuclear chromatin (inside RBC) Makes RBC with basophilic particles inside Cabot’s ring Remnants of nuclear membrane (artifact)

21. WBC or Leukocytes

22. Leukocytes or WBC Involved in the cellular and humoral defense of the organism against foreign materials Normal lifespan – a few days to a week Normal count – 6,000 to 10,000 per microliter of blood Divided into two groups: Granular Non-granular

23. Terminologies Diapedesis– a process that accounts for the unidirectional flow of granulocytes and monocytes thru intact walls of blood vessels Chemotaxis – attraction of specific cells by chemical mediators; migration of blood cells to the site of infection

24. Granular WBC

25. Neutrophils/Heterophils 60-70% 12-15 μm in diameter 2-5 lobes In females, the inactive x-chromosome appears as a drumstick appendage on one of the lobes of the nucleus (Barr body) First line of cellular defense (phagocytes) Normal lifespan – 1-4 days (6-7 hours halflife)

26. Eosinophils or Acidophils 2-4% Bilobed, with numerous large acidophilic granules Increase in number during parasitism and allergic reactions

27. Basophils Less than 1% 12-15 µm in diameter S-shaped nucleus obscured by large basophilic granules May supplement the function of mast cells in immediate hypersensitivity reaction

28. Non-granular WBC

29. Lymphocytes 6-8 µm (small), medium-sized and large-sized (18 μm) are present in circulating blood Diverse function, all related to immune reactions in defending against invading microorganism Lifespan – a few days The only leukocyte that return to the tissue after diapedesis 25 – 30%

30. Monocytes 12-20 µm in diameter U-shaped or kidney-shaped nucleus Precursor cells of the mononuclear phagocyte system 4-8%

31. Platelets or Thrombocytes

32. Thrombocytes Lightest formed elements Nonnucleated, disklike fragments 2-4 µm Promote blood clotting and help repair gaps in the walls of blood vessels, preventing blood loss Normal count – 200,000 to 400,000 per microliter of blood Normal lifespan – about 10 days