2. BLOOD Modified type of CT

3. Blood constituents: A. Blood plasma:55% of blood volume includes: 90 % water. 10 % : inorganic salts and organic substances: mainly plasma proteins (albumins, globulins, fibrinogen and prothromin).

4. B. blood elements: These constitute about 45 % of total blood volume. They are the: 1-red blood corpuscles (R.B.Cs) 2-the white blood cells (W.B.Cs) or leukocytes including a-the granular leucocytes (neutrophils, eosinophils, basophils) and b-the agranular leucocytes (lymphocytes, monocytes) 3-the blood platelets

5. Observation of a blood film

6. Red blood corpuscles (R.B.Cs)

7. R.B.Cs count: Average R.B.Cs count in normal males is 5 - 5.5 millions / mm 3 blood, whereas in females it is 4.5-5 millions / mm 3 blood. Life Span of R.B.Cs.: It is about 100-120 days..

9. Shape: biconcave discs. Nucleus: non nucleated. Size: their diameter ranges between 7.2-7.8  in blood films. It’s cytoplasm: contains Hemoglobin concentrated at the periphery.

10. Abnormalities in R.B.Cs.: Abnormalities in the number of R.B.Cs: i- Polycythaemia: i.e. increase in the total number of R.B.Cs. ii- Anaemia: i.e. decrease in the total number of R.B.Cs.

11. Abnormalities in the size of R.B.Cs.: Anisocytosis: when there are R.B.Cs. of variable sizes. i- Microcytes: when the diameter of R.B.Cs.is less than 6 . ii- Macrocytes: when the diameter of R.B.Cs.is more than 10 .

12. Poikilocytosis: when R.B.Cs present in a blood film with variable shapes. Sickle cell anaemia

13. Leucocytes Normal Count: The average total W.B.Cs. count is 4000-10000 / mm 3 blood.

14. Leucocytes (W.B.Cs)

15. Granular leukocytes A-Neutrophils B-Eosinophils C-Basophils

16. Neutrophils 66-70% of leukocytic count

17. Neutrophil Barr’s body

19. Functions of Neutrophils: P.N.Ls (neutrophils) are the first line of defense against any invading micro-organism

20. Abnormal Neutrophil Count: - Neutrophilia: i.e. abnormal increase in the number of neutrophils. This is observed in acute inflammations e.g. appendicitis, tonsillitis. -Neutropenia: i.e. abnormal decrease in the number of neutrophils e.g. in influenza, typhoid fever.

21. Eosinophils 1-4% of leukocytic count

24. Function of Eosinophils: They are responsible for regulation of allergic immune reactions.

25. Abnormal Eosinophil Counts: 1-Eosinophilia: i.e. abnormal increase in the number of eosinophils as in: - Allergic reactions e.g. asthma, urticaria -Parasitic infections e.g. Bilharziasis. 2-Eosinopenia: i.e. abnormal decrease in the number of eosinophils e.g. as result of prolonged corticosteroid therapy.

26. Basophils 0-1% of leukocytic count

28. Basophil

29. Function of Basophils: Basophils are responsible for the release of Histamine in systemic allergic reaction

30. Agranular leukocytes

31. Monocyte 3-8% Kidney-shaped nucleus platelets

33. Functions of Monocytes: Monocytes are phagocytic cells. Abnormal Monocytes Count: Monocytosis: is an abnormal increase in the number of blood monocytes. It occurs in diseases like malaria, typhus, viral infections

34. Monocyte Lymphocyte

35. Lymphocytes 20-25% Large, indented nucleus

37. Abnormal Lymphocytic Count: Lymphocytosis: It is an abnormal increase in the number of lymphocytes as in: -lymphatic leukaemia - chronic infections e.g. tuberculosis, syphilis, whooping cough.

38. Platelets 150,000-350,00/mm 3 (about ¼ - ½ million /mm 3 ).

39. Blood platelet

40. Function of Blood Platelets: Blood platelets are concerned with: - the process of thrombus formation (blood clotting) in response to any vascular endothelial injury to prevent excessive blood loss. - clot retraction and removal of the blood clot after healing of the vessel wall to re-establish the flow of the blood.

42. In an ideal blood smear you can identify many formed blood elements