Ch. 19 Cardiovascular system: The Blood

Monocytes

(Blue-Gray cytoplasm and Kidney shaped nucleus) -Differentiate into: ~Fixed Macrophages ~Wandering Macrophages

Lymphocytes

(Tiny, Stains dark) -T Cells -B cells -Natural Killer (NK) Cells

Blood typing

-Agglutination= clumping of RBC's (different than clotting) -Anti-A serum -Anti-B serum

Major Soldiers of immune system: Lymphocytes

-B cells -Develop into plasma cells, whic secret antibodies -Attacks bacteria -T cells -Attacks viruses, cancer cells, and transplanted tissues -Killer cells -Attack spontaneously arising tumor cells

Red Blood Cell Anatomy

-Biconcave discs -Lack nucleus and other organelles -Contain hemoglobin -Plasma Membranes ~Contain different glycolipids ~Antigens that account for various blood types

Basophils

-Blue-Purple granules -Nucleus usually not clearly visible

Coagulation

-Coagulation phase --Blood clotting -Actually a series of events -Clotting factors -Cascade of events: -Extrinsic pathway -Intrinsic pathway -Common pathway -Clot retraction

Red Blood Cell Physiology

-Contains no nucleus ~Therefore large surface area to transport oxygen -ATP generation- anaerobic ~Don't use the oxygen they transport -Shape of RBC ~Larger surface area for gas diffusion

Vascular spasm

-Contraction of vessel walls of damaged arteries or arterioles -Occurs immediately

Clot retraction

-Control of Hemostasis -Consolidation or tightening of fibrin clot -Pulls edges of damaged vessel closer together -Permanent repair takes place

Dissolution of Clot

-Control of Hemostasis -Fibrinolysis - dissolution of a clot -Pasminogen --> plasmin --> dissolves clot -Plasmin -Digests fibrin thread -Inactivates fibrinogen, prothrombin, and Factors V, VIII, and XII

Common pathway

-Development to Thrombin and Fibrin -Prothrombinase + Ca2+ converts Prothrombin --> Thrombin -Thrombin + Ca2+ --> fibrinogen --> fibrin -Thrombin also activates Factor XIII which strengthens fibrin threads into clot

Hemoglobin Structure

-Each RBC contains millions -Structure: Globin ~4 polypeptide chains (2 Alpha) (2 Beta) ~4 hemes (Fe2+)

Intrinsic pathway

-More complex; occurs w/in blood -Damage to endothelial cells exposes collagen fibers --> contact with collagen fibers activates Factor XII -Activated Factor XII + Ca2+ --> Factor X -Activated platelets --> platelet phospholipids + Ca2+ --> Factor X -Factor X + Ca2+ --> prothrombinase

Function of White Blood Cells

-Most WBC have a life span of only a few days -infection=only few hours -Normal Leukocyte levels (WBC Count) -5,000-10,000 cells per uL -Outnumbered by RBC's 700:1 -Combat pathogens -Phagocytosis -Immune Responses

Extrinsic pathway

-Occurs when blood has escaped into surrounding tissues -Tissue factor (TF) + Ca2+ --> Factor X + Factor V + ca2+ --> prothrombinase

Antigens (agglutinogens)

-On surface of erythrocytes -Blood groups based on presence or absence -Within blood groups, there may be 1-2 Blood types -Common blood groups: -ABO -Rh

Blood types and associated antigents

-Only Antigen A = Blood type A -Only Antigen B = Blood type B -Both Antigens A & B = Blood type AB -Neither Antigens A or B = Blood type O

Antibodies of Blood

-Opposites of Antigens -Won't have antibodies against own blood type/antigen -Antigen A/Type A= Antibodies B -Antigen B/Type B= Antibodies A -Antigens A&B/Type AB= No antibodies (universal recipients) -No Antigens/Type O= Antibodies A & B (universal donors)

Neutrophils

-Pale Lilac granules -Two to Five lobed nucleus -Neutrophils age=increase in nuclear lobes

Platelet phase (developing of platelet plug

-Platelet adhesion -Platelet release reaction -Platelet aggregation --Platelet plug formed

Eosinophils

-Red-Orange granules -Two-lobed nucleus

Rh Blood Group

-Rh antigen=Rh+ -No Rh antigen=Rh-

Hemostasis

-Sequence of responses to stop bleeding (involves platelets) -Three mechanisms contribute to hemostasis: 1. Vascular spasm 2. Platelet plug 3. Coagulation

Chemotaxis

1. Movement of cells or organisms in response to chemicals, whereby the cells are attracted (positive chemotaxis) or repelled (negative chemotaxis) by substances exhibiting chemical properties. 2. The migration of polymorphonuclear leukocytes and macrophages toward higher concentrations of certain fragments of complement.

Red Blood Cell Life Cycle (120 Days)

1. Phagocytosis of RBC ~Macrophages in spleen, liver, or red bone marrow 2. Hemes and globins separated: 3. Globin is a protein -Reused for protein synthesis ~Heme seperates into (Iron)-Fe3+ (Biliverdin) 4. Iron removed from heme (Fe3+) binds to transferrin -Fe3+ detaches from transferrin (carries Fe3+ in blood & attaches to ferritin (stores Fe3+ in liver) -Fe3+ reattaches to transferrin -Transferrin transports Fe3+ to bone marrow where it is recycled -Erythropoiesis --> RBC --> enter circulation 5. Non-iron portion of heme converted to biliverdin (green) then into bilirubin (yellow) -Bilirubin transported to liver -Bilirubin secreted by liver cells into bile --> sm intestine --> lg intestine -In lg intestin, converted to urobilinogen ~converted to urobilin (yellow)-excreted in urine ~converted to stercobilin (brown)- eliminated in feces

Blood Plasma Contents

1. Water (91.5%) 2. Proteins (7.0%) -Albumins (54%) -Globulins (38%) -Clotting proteins (7%) -Antibodies (sometimes) 3. Other Solutes (1.5%) -Electrolytes -Nutrients -Gases -Regulatory substances -Waste products

Formed Elements Contents

1. Whole Blood Cells -Red Blood Cells (RBC's)-Erythrocytes -White Blood Cells (WBC's)-Leukocytes ~Granular (Basophils, Eosinophils, Neutrophils) ~Agranular (Lymphocytes and Monocytes) 2. Fragments -Platelets - thrombocytes

Biliverdin

A green bile pigment formed from the oxidation of heme; a bilin with a structure almost identical to that of bilirubin.

RBC

A normal, mature RBC has no nucleus and is only about 7.5 μm in diameter. More than 1500 of them could be placed side by side in a 1 cm space. Before the cell reaches maturity and enters the bloodstream from the bone marrow, the nucleus is extruded, mature RBCs are shaped like tiny biconcave disks, does not contain ribosomes, mitochondria, and other organelles typical of most body cells, primary component of each RBC is the red protein pigment, hemoglobin. It accounts for more than one third of the cell volume and is critically important to its primary function.

Progenitor cell

A progenitor cell is a biological cell that, like a stem cell, has a tendency to differentiate into a specific type of cell, but is already more specific than a stem cell and is pushed to differentiate into its "target" cell.

Pluripotent stem cell

Pluripotent stem cells are master cells. They're able to make cells from all three basic body layers, so they can potentially produce any cell or tissue the body needs to repair itself. This "master" property is called pluripotency. Like all stem cells, pluripotent stem cells are also able to self-renew, meaning they can perpetually create more copies of themselves.

Function of RBC

RBCs play a critical role in the transport of oxygen and carbon dioxide in the body

Stercoblin

Stercobilin is a tetrapyrrolic bile pigment and is one end-product of heme catabolism. It is the chemical responsible for the brown color of human feces and was originally isolated from feces in 1932

Clotting factors

Substances in the blood that act in sequence to stop bleeding by formin, the chemical and cellular constituents of the blood responsible for the conversion of fibrinogen into a mesh of insoluble fibrin causing the blood to coagulate or clot.

Blood plasma

The fluid portion of blood; one of the three major body fluids (interstitial and intracellular fluids are the other two). Totals about 55% of blood volume.

Urobilinogen

Urobilinogen is a colourless by-product of bilirubin reduction. It is formed in the intestines by bacterial action on bilirubin.

Thrombopoietin

a colony-stimulating factor that is the humoral regulator of the production of platelets.

Platelet

a small colorless disk-shaped cell fragment without a nucleus, found in large numbers in blood and involved in clotting.

Precursor cell

also called a blast cell or simply blast, is a type of partially differentiated, usually unipotent cell that has lost most or all of the stem cell multipotency. Usually a precursor cell is a stem cell which has the capacity to differentiate into only one cell types.

Agranular leukocyte

also known as mononuclear leukocytes, are white blood cells with a one-lobed nucleus. They are characterized by the absence of granules in their cytoplasm, which distinguishes them from granulocytes. Normal hematologic blood values of MLs are about 35% of all white blood cells.

Transfusion

an act of transferring donated blood, blood products, or other fluid into the circulatory system of a person or animal.

Agglutinogen

an antigen that stimulates the production of an agglutinin.

Leukocytosis

an increase in the number of white cells in the blood, especially during an infection.

Globin

chain of four proteins; binds to a red pigment (heme) to form hemoglobin

Cytokines

chemical released from cells to trigger or regulate innate and adaptive immune responses

Thrombopoietin

glycoprotein hormone produced by the liver and kidney which regulates the production of platelets. It stimulates the production and differentiation of megakaryocytes, the bone marrow cells that bud off large numbers of platelets.

Erythropoietin

glycoprotein secreted to increase red blood cell production in response to oxygen deficiency

Heme

iron-containing chemical group found in hemoglobin; temporarily binds to oxygen

Hemoglobin

iron-containing protein in red blood cells responsible for their oxygen-carrying capacity. Packed within each RBC are an estimated 200 to 300 million molecules of hemoglobin, which make up about 95% of the dry weight of each cell. Each hemoglobin molecule is composed of four protein chains. Each chain, called a globin, is bound to a red pigment, identified in Figure 20-5, as a heme group. Each heme group contains one iron atom. Therefore one hemoglobin molecule contains four iron atoms.

Thrombosis

local coagulation or clotting of the blood in a part of the circulatory system.

Hematopoiesis

process of blood cell formation

Erythropoiesis

process of red blood cell formation

Phagocytosis

the engulfing of microorganisms or other cells and foreign particles by phagocytes

Fibrinolysis

the enzymatic breakdown of the fibrin in blood clots.

Emigration

the escape of leukocytes through the walls of small blood vessels; diapedesis.

Hemolysis

the rupture or destruction of red blood cells.

Granular leukocyte

they are better known as granulocytes -- are part of the innate immune system and have somewhat non specific, broad-based activity. They do not respond exclusively to specific antigens, as do B-cells and T-cells. Neutrophils, eosinophils and basophils are all types of granulocytes.

Hematocrit

volume percent of blood cells in whole blood; packed cell volume

Bilirubin

yellowish pigment formed when the heme group is removed from the hemoglobin molecule and stripped of its iron atom; a product of the breakdown of red blood cells