cardiovascular system blood. blood – general characteristics blood is c.t. plasma = liquid matrix...
TRANSCRIPT
CARDIOVASCULAR SYSTEM
Blood
Blood – General Characteristics
Blood is C.T.Plasma = Liquid Matrix55% 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 literspH = 7.35 to 7.45Formed Elements:
- Erythrocytes (RBCs)
- Leukocytes (WBCs)
- Thrombocytes (Platelets)
Blood - Functions
Transports (Gases, Nutrients, Hormones)Regulates pH & Electrolyte Balance in
Interstitial FluidPrevents Fluid Loss from BleedingDefends against Pathogens & ToxinsAids in Body Temperature Regulation
Components - Plasma
Liquid Component of Blood92% Water7% 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 CellBiconcave Discs (shaped like “LifeSaver”)Shape increases Surface Area/Volume
RatioAnucleate when matureLive 120 Days
Figure 17.3
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)
Erythrocytes - continued
Hematocrit = % RBCs in BloodRBC Count = # RBCs/mm3
- Males: 4.6 – 6.2 X 106/mm3
- Females: 4.2 – 5.4 X 106/mm3
2 million produced/secondHumans have over a trillion RBCsBlood is 4X thicker than waterProduction with O2 or Blood Loss
Fate of ErythrocytesFate of Erythrocytes
Slide 10.15
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 O2 Delivery- Cyanosis, Blood Clots
Components - Leukocytes
White Blood Cells (WBCs)Defend Against MicrobesUse Blood for Transport, But Occur
Mostly Outside Circ. System in TissuesDiapedesis – Squeeze through Capillary
WallsAmeboid Motion to move once outside
bloodstream
Leukocytes - continued
Chemotaxis – Chemicals released from sites of damage or inflammation attract WBCs
Phagocytosis – ingestion of bacteria, debrisFive Types Based on:
- Size- Nuclear Shape- Cytoplasmic Granules- Affinity for Stain
Types of LeukocytesTypes 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:
* Neutrophils65% of Circulating WBCsNucleus 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 WBCsOrange/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
* Basophils½ - 1% of Circulating WBCsDark 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:
* Monocytes3-9% in Circulating WBCsLargest WBCNucleus is Kidney-bean, oval in
shapeBecome Phagocytic Macrophages
Types of Leukocytes
L to R: lymphocyte, basophil, monocyte, neutrophil, eosinophil
Leukocyte Types - continued
* Lymphocytes30% Circulating WBCsSmallest WBCLarge, Spherical Nucleus, Little
CytoplasmProduce Antibodies
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)
HematopoiesisHematopoiesis
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/mm3
Active in Hemostasis (Stoppage of Bleeding)
Hematopoiesis (Hemopoiesis)
Process of Blood Cell FormationOccurs in Yolk Sac, Liver & Spleen
(fetus); Red Bone Marrow (adult)Involves Stem Cells (Hemocytoblasts) &
Series of StepsErythropoietin = Kidney Hormone,
RBCs
HematopoiesisHematopoiesis
Slide 10.10a
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Hemostasis
Stoppage of BleedingRequires Vitamin K and Ca2+
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 Ca2+ & 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
InheritedInvolves 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 AA Antigen Only41% of US
* Type BB Antigen Only9% US
ABO Typing - continued
* Type ABBoth A & B Antigens3% USUniversal Recipient
* Type ONeither Antigen47% USUniversal 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 OType B can receive: Type B, Type OType AB can receive: Types A, B, AB, OType 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 2nd Rh+ Fetus, Anti-Rh Passes from Mom to Fetus
- Fetal RBC Destruction
- Rhogam Prevents Mom from Producing Anti-Rh