Hematology blood synthesis fe synthesis

Bloody

1. Blood Physiology

2. Blood Blood is a type of connective tissues. It consist of : 1- Cells (cellular part) 2- plasma (fluid part ) The cells are: Red blood cells (RBCs) or erythrocytes. White blood cells (WBCs) or leukocytes. Platelets or thrombocytes.

3. Volume of blood is about 5 litters in an average adult male. 8% of the total body weight. Volume of plasma is about 3.5 L (5% of total body weight ) Formation in blood : I n adults : mainly in the bone marrow

4. Hematopoiesis (formation of blood)

5. The packed cell volume(PCV) The cells in the blood can be separated by centrifugation. The percentage of cells in blood is called the packed cell volume (PCV) or the hematocrit. Most of these cells are RBCs (99.9%). Normal values : - male 40-50% - Females 37-47%

6. Low PCV indicate anemia High PCV indicates polycythemia.

7. Functions of blood 1- Transport of : Gases (e.g. oxygen & carbon dioxide). Nutrients (e.g. glucose, amino acids & free fatty acids ). Waste products (e.g. urea & uric acid). Hormones (e.g. insulin & cortisol)

8. 2- Defense by WBCs and antibodies . 3 - Hemostasis: - prevention of blood loss & maintenance of blood in fluid state .

9. Characteristics of RBCs:- Shape: biconcave disks. Diameter :7.5 micrometer. Content : no nucleus & no organelles. Life span= 120 days Each cell contains hemoglobin RBCs count: male 4.8 – 5.8 million/mm³ . female 4.2 – 5.2 million/mm³ Red blood cell (Erythrocyte)

10. Functions of RBCs Transport oxygen. Transport carbon dioxide. Contains buffers (Hemoglobin) to control pH.

11. Control of Erythropoiesis (formation of RBCs) Normal erythropoiesis requires: 1- normal bone marrow 2- certain hormones (erythropoietin) 3- nutrients(e.g. iron, folic acid, and vitamins )

12. Hemoglobin( Hb ) The red pigment within the RBCs. Its concentration in the blood : 14-16 g/dl in adult males 13-15 g/dl in adult females. 18-20 g/dl in neonates.

13. Functions of Hb Carries 98% of oxygen in the blood. Carries some carbon dioxide. Buffer.

14. Normal types of Hb 1-Hb A:- Adult Hb = 98% of all Hb in adults. 2- Hb A2:- Adult Hb = 2 % of all Hb in adults . 3- Hb F :- Fetal Hb Replaced by Hb A at 6 months after birth. Hb F has higher affinity to oxygen than Hb A. 4- HbA1c:- Subtype of Hb A, bound with the glucose. Its excess indicates poor control of diabetes mellitus.

15. Abnormal types of Hb Hb S :- Sickle cell Hb. It is a Hb A but the amino acid number 6 in beta chain (glutamic acid) is replaced by ( valine ).

16. Anemia The definition :- State of reduction in Hb concentration below the normal range. The symptoms :- Headache. Weakness & fatigability. Palpitation. Pallor in the skin & mucous membranes.

17. Causes of anemia :- 1- Decreased production : Bone marrow diseases e.g. tumors. Lack of nutrients e.g. iron, vitamin B12 and folic acid 2- Increased destruction :- as in sickle cell and malaria 3- Blood loss

18. White blood cell (leucocytes ) (WBCs ) The motile units in the blood that protect the body against invaders A larger blood cell. Contains nucleus, mitochondria. Normal count: 4000-11000/mm³

19. Functions of WBCs Defense against : 1- Bacterial infections 2- Parasitic infections 3- Viral infections 4- Tumors

20. Classification Are two types:- 1-Granulocytes 2-A granulocytes

21. Granulocytes Have granulated cytoplasm Polysegmented nucleus Shorter life span (Hours)

22. Types of Granulocytes Neutrophils: the granules react with basic and acidic dyes Eosinophils (Acidophils): the granules react with acidic dyes (eosin) Basophils: the granules react with basic dyes

23. Neutrophil : Constitute 50-70% of total WBCs Nucleus: segmented (3-5 lobes) Cytoplasm: granulated Granules: purple functions:- phagocytosis of bacteria Increased in: Acute bacterial infections

24. Eosinophil : Constitute 1-4% of total WBCs Nucleus: segmented ( 2 lobes) Cytoplasm: granulated Granules: Red Increased in : parasitic infections

25. Basophils Constitute 0-0.4% of total WBCs Nucleus: segmented (hidden by the granules ) Large cytoplasmic granules contain heparin, histamine Increased in allergic reactions

26. Agranulocytes Generally have no granules in the cytoplasm Have one nucleus (not segmented ) Types of Agranulocytes: Monocytes Lymphocytes

27. Monocyte Larger diameter than other types of WBCs Constitute 2-8% of total WBCs Nucleus: kidney shape Cytoplasm: no granules Function: macrophages (phagocytosis)

28. Lymphocyte Constitute 20-40% of total WBCs Nucleus: rounded Cytoplasm : no granules Function: Responsible for immunity . T lymphocytes: cellular immunity B lymphocytes: humoral immunity

29. Hemostasis

30. HEMOSTASIS Definition : Prevention of blood loss by arrest of bleeding and maintenance of blood in fluid state . Mechanisms of hemostasis: Vasospasm (vasoconstriction) Formation of platelet plug Formation of blood clot ( coagulation). Fibrinolysis or fibrous tissues formation.

31. Platelets Small cells (2-4 micrometer in diameter). Count : 150.ooo-400.ooo/mm3. They circulate in the blood in an inactive state

32. Blood grouping Definition: is classification of blood based on the presence or absence of inherited antigen on the surface of red blood cells (RBCs).

33. Importance : 1-Blood transfusion 2-Exclusion of paternity Blood systems: 1- ABO system 2- Rh system ( Rhesus)

34. ABO system

35. People with blood group (O ⁻) are called " universal donors" and people with blood group (AB ⁺ ) are called " universal receivers."

36. Rhesus Factor (Rh Factor ) Besides the ABO system, a person can be either… Rh positive ( there is antigen D ) Rh negative ( No antigen D )