1. CARDIOVASCULAR SYSTEM
Blood

2. Blood – General Characteristics
Blood is C.T.
Plasma = Liquid Matrix
55% Plasma, 45% Formed Elements (Cellular)
Formed via Hematopoiesis (Stem Cells in Bone Marrow give rise to Cell types)

3. General Characteristics continued
Avg. Vol. = 5 liters
pH = 7.35 to 7.45
Formed (cellular) Elements:
Erythrocytes (RBCs)
Leukocytes (WBCs)
Thrombocytes (Platelets)

5. Blood - Functions Transports (Gases, Nutrients, Hormones, Wastes)
Regulates pH & Electrolyte Balance in Interstitial Fluid
Prevents Fluid Loss from Bleeding
Defends against Pathogens & Toxins
Aids in Body Temperature Regulation

6. Components - Plasma Liquid Component of Blood 91% Water 7% Proteins:
Albumins (Most Abundant, Osmotic Pressure)
Globulins (Antibodies, Transport Proteins, Lipoproteins)
Fibrinogen (Clotting)
2% Inorganic Salts, Carbohydrates, Lipids, Hormones, Gases, Wastes, etc.
Globulins: Transport of fat-soluble vitamins (B12), steroid hormones (cortisol, thyroid hormones)

8. Components - Erythrocytes
Red Blood Cells (RBCs)
Most Abundant Blood Cell
Anucleate when mature
Biconcave Discs (shaped like “LifeSaver”)
Shape increases Surface Area/Volume Ratio
Live 120 Days

9. Erythrocytes - continued
Hemoglobin (Hb)
Red Pigment
Contains 4 Heme
Groups (Fe++)
Reversibly binds Oxygen
In High [O2], Binds O2  OxyHb (Bright Red)
In Low [O2 ], Releases O2  DeoxyHb (Darker)
Each RBC contains about 280 million hemoglobin molecules.

10. Erythrocytes - continued
Hematocrit = % RBCs in Blood
RBC Count = 5 million/mm3
2 million produced/second
Humans have over a trillion RBCs
Blood is viscous (4X thicker than water)
Production  with  O2 or Blood Loss

12. Fate of Erythrocytes Unable to divide, grow, or synthesize proteins
Wear out in 100 to 120 days
Removed by phagocytes in the spleen or liver
New RBCs made by stem cells in bone marrow

14. Erythrocyte Disorders
Anemia (RBC or Hb Deficiency)
Hemorrhagic (Blood Loss)
Hemolytic (RBC Destruction)
Aplastic ( Bone Marrow Function)
Sickle Cell (Inherited Hb Mutation)
Polycythemia (Abnormal  in RBCs)
 Viscosity & B.P. with  O2 Delivery
Cyanosis, Blood Clots
Pernicious Anemia – lack intrinsic factor (& poor Vitamin B12 absorption) from stomach mucosa
Iron deficiency Anemia – lack of dietary iron, heavy menstrual bleeding, chronic bleeding ulcer

15. Components - Leukocytes
White Blood Cells (WBCs)
Defend Against Microbes
Use Blood for Transport, But Occur Mostly Outside Circ. System in Tissues
Diapedesis – Squeeze through Capillary Walls
Ameboid Motion to move once outside bloodstream

16. Diapedesis of WBCs

17. Leukocytes - continued
Chemotaxis (positive) – Chemicals released from sites of damage or inflammation attract WBCs
Phagocytosis – ingestion of bacteria, debris
Five Types Based on:
Size
Nuclear Shape
Cytoplasmic Granules
Affinity for Stain

18. Positive Chemotaxis in WBCs

19. Types of Leukocytes

20. Leukocyte Types Granulocytes Cytoplasmic Granules
Differential Staining of Granules
Approx. 2X Size of RBC
3 Types:
Neutrophils
Eosinophils
Basophils

21. Types of Granulocytes Neutrophils (PMN) 65% of circulating WBCs
Nucleus has 2-5 lobes
Neutral Rxn to stain (light pink to purple)
Phagocytic
 in Bacterial Infections

22. Types of Granulocytes Eosinophils (Acidophils)
2-4% of circulating WBCs
Bilobed Nucleus
Reddish-to-orange granules
Active in Detoxifying Foreign Proteins
 in Allergies, Parasitic Infections

23. Types of Granulocytes Basophils 0.5-1% of circulating WBCs
Bilobed Nucleus
Blue-violet granules
Granules contain histamine & heparin
Intensify inflammation

24. Leukocyte Types Agranulocytes No apparent granules
Most variable in size
2 Types:
Lymphocytes
Monocytes

25. Types of Agranulocytes
Lymphocytes
20-25% of circulating WBCs
Smallest WBC
Large, spherical nucleus, little cytoplasm
Immune response, produce antibodies
Include: B-cells, T-cells, & Natural Killer cells

26. Types of Agranulocytes
Monocytes
3-8% of circulating WBCs
Kidney-shaped or C-shaped nucleus
Abundant cytoplasm
Largest leukocyte
Differentiate into phagocytic Macrophages

27. Components - Platelets
Cellular fragments of Megakaryocytes (reside in bone marrow)
300,000/mm3
Active in Hemostasis
Contain actin & myosin; able to contract
Platelets live for 5-9 days. Form from myeloid stem cells + thrombopoietin /hormone produced by liver  megakaryoblasts  megakaryocytes  platelets (2000 – 3000) .
Removed by macrophages in spleen & liver.

28. Hematopoiesis (Hemopoiesis)
Process of Blood Cell Formation
Occurs in Yolk Sac (embryo), Liver & Spleen (fetus); Red Bone Marrow (adult)
Involves Stem Cells (Hemocytoblasts) & Series of Steps
Erythropoietin = Kidney Hormone,  RBCs
Also in thymus & lymph nodes of fetus. Red bone marrow becomes primary site last 3 months before birth.

32. Leukocyte Disorders Normal WBC Count 5,000 – 10,000/mm3
Leukemia – Uncontrolled Production of WBCs with Immature WBCs in Circulation
Myeloid (  Granulocytes from Myeloid Stem Cells)
Lymphoid (  Lymphocytes from Lymphoid Stem Cells)

33. Hemostasis Stoppage of Bleeding Fast & localized
Involves many clotting factors
3 Phases:
Vascular Spasm
Narrows vessel, decreasing flow & loss
Caused by damage to vessel or neurotransmitter from platelets
Vascular spasm occurs in arteries & arterioles, and is effective for several minutes to several hours. Calcium ions assist in the activation of a variety of clotting factors.
K+ not involved in actual clot formation but is required for the synthesis of 4 clotting factors by liver cells.
Thrombolytic agents (streptokinase from bacteria & t-PA a synthetic form of plasmin)
Platelets release thromboxanes which stimulate vascular spasms;
endothelin, a peptide released from endothelium of vessels also stimulates vascular spasms

34. Steps in Hemostasis

35. Hemostasis - continued
Platelet Plug
Platelets Become Sticky & Adhere to Endothelium, Collagen, & to One Another
Coagulation (Blood Clotting)
Most Effective, But Delayed
1 – platelets adhere to exposed collagen (mediated by a protein)
2 – once adhered/aggregated, platelets release chemicals (thromboxane & ADP) which activate other platelets, which in turn adhere, aggregate & release same chemicals.
3 – activated platelets produce receptors for fibrinogen & fibrinogen binds many platelets together, forming a platelet plug

36. Steps in Hemostasis

37. Coagulation Formation of Prothrombin Activator (PA)
PA converts Prothrombin into Thrombin
Thrombin converts Fibrinogen into Fibrin
Fibrin sticks to damaged blood vessel, forms meshwork
Platelets, blood cells stick to meshwork, clot forms
Clot retracts, pulling damaged edges together
Injured tissues release tissue factor (TF). TF interacts with K+, Ca2+, platelets (PF3 a phospholipid) to form prothrombin activator.
Retraction pulls damaged edges of blood vessel back together, protects against infection & promotes healing. Serum leaks from clot during retraction; serum is plasma minus platelets & clotting factors.

39. Steps in Hemostasis

41. Abnormal Clot Formation
Thrombus – Clot Formed in Uninjured Vessel
Embolus – Thrombus, Broken Loose & Moved
Pulmonary Embolism (Lung Clot, Formed Elsewhere)
Coronary Embolism (Clot in Coronary Vessel, Formed Elsewhere)
Thrombi usually form in veins & may dissolve spontaneously. Emboli are not limited to dislodged blood clots; air bubbles, fat from broken bone, debris may act as emboli.

42. Thrombus in Artery

43. Human Blood Types Inherited
Involves Identifying Antigens on cell membrane of RBCs (Agglutinogens)
Must Avoid Agglutination (RBC Clumping due to Antigen-Antibody Reaction)
ABO and Rh Typing Significant in Transfusions

44. ABO Typing - continued ABO Typing Based on 2 Agglutinogens:
A Antigen & B Antigen
4 Types:
Type A
A Antigen Only
41% of US
Type B
B Antigen Only
9% US
The A & B antigens are glycolipids.

45. ABO Typing - continued Type AB Both A & B Antigens 3% US
Universal Recipient
Type O
Neither Antigen
47% US
Universal Donor

46. ABO Typing - continued Antibodies (Agglutinins) In Plasma
Appear Spontaneously After Birth
Only produced if the antigen is foreign
React with antigen if the 2 are mixed
2 Types:
Anti-A (in Types B, O)
Anti-B (in Types A, O)

48. ABO Typing - continued
Compatibility involves Matching RBCs of Donor (i.e.Antigens) & Immune System (Potential Antibodies) of Recipient
Type A can receive: Type A, Type O
Type B can receive: Type B, Type O
Type AB can receive: Types A, B, AB, O
Type O can Receive: Type O

49. Blood Typing

50. Human Blood Types - continued
Rh Typing Based on surface antigen on RBC (Rh factor or antigen D)
If antigen present, Rh+
If antigen absent, Rh-
Antibodies appear in Rh- persons only after exposure. Subsequent exposure results in agglutination.

51. Rh Typing - continued Hemolytic Disease of the Newborn (HDN)
A.K.A Erythroblastosis Fetalis
Occurs when Rh- Mom Pregnant with Rh+ Fetus
Mixing of Maternal & Fetal Blood occurs at Birth
Mom then Starts to Produce Anti-Rh
With 2nd Rh+ Fetus, Anti-Rh Passes from Mom to Fetus
Fetal RBC Destruction
Rhogam Prevents Mom from Producing Anti-Rh