1. Martin ponciano, lvn, dsd, ms
Hematologic system
Martin ponciano, lvn, dsd, ms

2. Blood Only liquid connective tissue in the body
Blood accounts for approximately 8% of body weight
Average volume: 5–6 L for males, and 4–5 L for females
3 Main functions
Transportation
Regulation
Protection

3. Transportation Gases Food Material (Nutrients) Waste
Cellular products (Hormones

4. Regulation pH Body Temperature Tissue Volume
Range of blood pH = 7.35 — 7.45
Body Temperature
Blood maintains normal body temperature by absorbing and distributing heat
Tissue Volume
Blood maintains adequate fluid volume in the circulatory system

5. Protection Blood prevents blood loss by: Blood prevents infection by:
Activating plasma proteins and platelets
Initiating clot formation when a vessel is broken
Blood prevents infection by:
Synthesizing and utilizing antibodies
Activating complement proteins
Activating WBC’s to defend the body against foreign invaders

6. Composition Formed Elements (45%) Plasma (55%) Erythrocytes (RBC’s)
O2transportation
Leukocytes (WBC’s)
Different types
Protects against infection
Thrombocytes (Platelets)
Participate in blood clotting
Plasma (55%)
91% water
8% Proteins
Albumin
Clotting Factors
Antibodies
Complement Proteins

7. Components of Whole Blood
Med. Term pg. 135 Figure 5.13
A&P pg. 281 Figure 13-1

8. Components of Whole Blood
Figure 17.2

9. Formed Elements Produced in red bone marrow (hematopoietic tissue)
Where is red bone marrow located in the long bone?

10. Erythrocytes (RBCs)
Figure 17.3

11. Erythrocytes (RBCs)
Biconcave discs, anucleate, essentially no organelles
Filled with hemoglobin (Hb), a protein that functions in gas transport and contains iron
RBC production is stimulated by the hormone erythropoietin (EPO)
EPO is released from kidney
Release in response to decrease in oxygen

12. Erythropoietin Mechanism
Imbalance
Start
Homeostasis: Normal blood oxygen levels
Stimulus: Hypoxia due to
decreased RBC count,
decreased amount of
hemoglobin, or decreased
availability of O2
Imbalance
Increases
O2-carrying
ability of blood
Reduces O2 levels
in blood
Enhanced
erythropoiesis
increases
RBC count
Kidney (and liver to a smaller
extent) releases erythropoietin
Erythropoietin
stimulates red
bone marrow

13. Leukocytes (WBCs)
Leukocytes, the only blood components that are complete cells:
Are less numerous than RBCs
Make up 1% of the total blood volume
Move through tissue spaces

14. Granulocytes Granulocytes – neutrophils, eosinophils, and basophils
Contain cytoplasmic granules that stain specifically (acidic, basic, or both) with Wright’s stain
Are larger and usually shorter-lived than RBCs
Are all phagocytic cells
Cells that perform phagocytosis
(Review) Phagocytosis: process of destroying pathogens by surrounding and destroying pathogens

15. Neutrophils Most common leukocyte type Functions as a phagocytic cell
Protects against bacteria, viruses, and fungi

16. Eosinophils Eosinophils account for 1–4% of WBCs
Lead the body’s counterattack against parasitic worms
Lessen the severity of allergies by phagocytizing immune complexes

17. Basophils Account for 0.5% of WBCs and:
Have large, purplish-black (basophilic) granules that contain histamine
Histamine – inflammatory chemical that acts as a vasodilator and attracts other WBCs (antihistamines counter this effect)
Responsible for allergic reactions and inflammatory reactions

18. Agranulocytes Agranulocytes – lymphocytes and monocytes:
Lack visible cytoplasmic granules
Are similar structurally, but are functionally distinct and unrelated cell types

19. Lymphocytes Account for 25% or more of WBCs and:
Are found mostly enmeshed in lymphoid tissue (some circulate in the blood)
There are two types of lymphocytes: T cells and B cells
T cells function in the immune response
B cells give rise to plasma cells, which produce antibodies

20. Monocytes Monocytes account for 4–8% of leukocytes
They are the largest leukocytes
They leave the circulation, enter tissue, and turn into macrophages

21. Macrophages Macrophages: Are highly mobile and actively phagocytic
Activate lymphocytes to mount an immune response

22. Leukocytes
Figure 17.10

23. Platelets Platelets are fragments of megakaryocytes
Giant bone marrow cells
Platelets function in the clotting mechanism by forming a temporary plug that helps seal breaks in blood vessels

24. Summary of Formed Elements
Table

25. Summary of Formed Elements
Table

26. Hemostasis A series of reactions for stoppage of bleeding
During hemostasis, three phases occur in rapid sequence
Vascular spasms – immediate vasoconstriction in response to injury
Platelet plug formation
Coagulation (blood clotting)

27. Blood Clotting Procoagulants Anticoagulants Fibrinogen Fibrin
Prothrombinase
Thrombin

31. Erythrocytes trapped in fibrin mesh

32. Human Blood Groups
RBC membranes have glycoprotein antigens on their external surfaces
These antigens are:
Unique to the individual
Recognized as foreign if transfused into another individual
Promoters of agglutination and are referred to as agglutinogens
Presence or absence of these antigens is used to classify blood groups

33. ABO Blood Groups The ABO blood groups consists of:
Two antigens (A and B) on the surface of the RBCs
Two antibodies in the plasma (anti-A and anti-B)
ABO blood groups may have various types of antigens and preformed antibodies

34. ABO Blood Groups
Table 17.4

35. Transfusion Reactions
Transfusion reactions occur when mismatched blood is infused
Donor’s cells are attacked by the recipient’s plasma agglutinins causing:
Diminished oxygen-carrying capacity
Clumped cells that impede blood flow
Ruptured RBCs that release free hemoglobin into the bloodstream

36. Transfusion Reactions
Circulating hemoglobin precipitates in the kidneys and causes renal failure

37. Blood Typing
When serum containing anti-A or anti-B agglutinins is added to blood, agglutination will occur between the agglutinin and the corresponding agglutinogens
Positive reactions indicate agglutination

38. Blood type being tested
Blood Typing
Blood type being tested
RBC agglutinogens
Serum Reaction
Anti-A
Anti-B AB
A and B + B – A O
None

40. Complete Blood Count (CBC)
Test that measures the following:
The number of red blood cells (RBCs)
The number of white blood cells (WBCs)
The total amount of hemoglobin in the blood
The fraction of the blood composed of red blood cells (hematocrit)