CARDIOVASCULAR SYSTEM Blood

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

General Characteristics continued Avg. Vol. = 4.5 to 5.5 liters pH = 7.35 to 7.45 Formed Elements: -Erythrocytes (RBCs) -Leukocytes (WBCs) -Thrombocytes (Platelets)

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

Components - Plasma Liquid Component of Blood 92% Water 7% Proteins: -Albumins (Most Abundant, Osmotic Pressure) -Globulins (Antibodies, Transport Proteins, Lipoproteins) -Fibrinogen (Clotting) 1- 2% Inorganic Salts, Carbohydrates, Lipids, Hormones, Gases, Wastes, etc.

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

Figure 17.3

Erythrocytes - continued Hemoglobin (Hb) -Red Pigment -Contains 4 Heme Groups (Fe ++ ) -Reversibly binds Oxygen -In High [O 2 ], Binds O 2  OxyHb (Bright Red) -In Low [O 2 ], Releases O 2  DeoxyHb (Darker)

Erythrocytes - continued Hematocrit = % RBCs in Blood RBC Count = # RBCs/mm 3 -Males: 4.6 – 6.2 X 10 6 /mm 3 -Females: 4.2 – 5.4 X 10 6 /mm 3 2 million produced/second Humans have over a trillion RBCs Blood is 4X thicker than water Production  with  O 2 or Blood Loss

Fate of Erythrocytes Slide Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  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

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  O 2 Delivery -Cyanosis, Blood Clots

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

Leukocytes - continued Chemotaxis – 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

Types of Leukocytes Slide 10.10a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Leukocyte Types Granulocytes -Cytoplasmic Granules -Differential Staining of Granules -Approx. 2X Size of RBC -3 Types: *Neutrophils  65% of Circulating WBCs  Nucleus has 2-5 Lobes

Types of Leukocytes L to R: lymphocyte, basophil, monocyte, neutrophil, eosinophil

Leukocyte Types - continued  Neutral Rxn to Stain (Light Pink to Purple)  Phagocytes   in Bacterial Infections *Eosinophils (Acidophil)  1-3% of Circulating WBCs  Orange/Red Granules (Acidic Rxn)  Bilobed Nucleus

Types of Leukocytes L to R: lymphocyte, basophil, monocyte, neutrophil, eosinophil

Leukocyte Types - continued  Active in Detoxifying Foreign Proteins   in Allergies, Parasitic Infections *Basophils  ½ - 1% of Circulating WBCs  Dark Blue/Black Granules (Basic Rxn)  Granules Contain: Histamine, Heparin, Seratonin

Types of Leukocytes L to R: lymphocyte, basophil, monocyte, neutrophil, eosinophil

Leukocyte Types - continued Agranulocytes -No Staining Granules -2 Types: *Monocytes  3-9% in Circulating WBCs  Largest WBC  Nucleus is Kidney-bean, oval in shape  Become Phagocytic Macrophages

Types of Leukocytes L to R: lymphocyte, basophil, monocyte, neutrophil, eosinophil

Leukocyte Types - continued *Lymphocytes  30% Circulating WBCs  Smallest WBC  Large, Spherical Nucleus, Little Cytoplasm  Produce Antibodies

Leukocyte Disorders Normal WBC Count 5,000 – 10,000/mm 3 Leukemia – Uncontrolled Production of WBCs with Immature WBCs in Circulation -Myeloid (  Granulocytes from Myeloid Stem Cells) -Lymphoid (  Lymphocytes from Lymphoid Stem Cells)

Hematopoiesis Slide 10.10a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Components - Thrombocytes Cellular fragments (Megakaryocyte reside in bone marrow) 130,000 – 360,000/mm 3 Active in Hemostasis (Stoppage of Bleeding)

Hematopoiesis (Hemopoiesis) Process of Blood Cell Formation Occurs in Yolk Sac, Liver & Spleen (fetus); Red Bone Marrow (adult) Involves Stem Cells (Hemocytoblasts) & Series of Steps Erythropoietin = Kidney Hormone,  RBCs

Hematopoiesis Slide 10.10a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Hemostasis Stoppage of Bleeding Requires Vitamin K and Ca 2+ 3 Phases: -Vascular *Blood Vessel Spasm *Direct Stimulus to Vessel or Neurotransmitter from Platelets *Small Vessels

Hemostasis - continued -Platelet *Platelet Plug Formation *Platelets Become Sticky & Adhere to Endothelium, Collagen, & to One Another *Larger Vessels -Coagulation (Blood Clotting) *Most Effective, But Delayed

Coagulation - continued *Complex, Multi-substance, Multi-step  Prothrombin Activator (PA or thromboplastin) Released by Damaged Tissue & Platelets  PA (with Ca 2+ & other factors) Converts Prothrombin into Thrombin  Thrombin Converts Fibrinogen into Fibrin (Insoluble)

Coagulation - continued  Fibrin Sticks to Damaged Edges, Forms Meshwork  Platelets, Blood Cells Stick to Meshwork, Clot Forms  Clot Later Retracts, Squeezes out Serum (plasma minus fibrinogen, & other clotting factors)

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)

Thrombus in Artery

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

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

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

ABO Typing - continued Antibodies (Agglutinins) -In Plasma -Appear Spontaneously After Birth -Bind to Foreign Antigens -2 Types: *Anti-A (in Types B, O) *Anti-B (in Types A, O)

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

Blood Typing

Human Blood Types - continued Rh Typing Based on Factor Present on RBC If Factor Present, Rh+ If Factor Absent, Rh- Antibodies appear in Rh- persons only after exposure. Subsequent exposure results in agglutination.

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