Blood Study Guide

Explain the diagnostic importance of blood testing

-Antibodies "protect" our bodies from "foreign" blood cells -Cross-reactions (transfusion reactions) can block blood vessels to vital organs with agglutinated RBCs or cell fragments

Describe the composition and physical characteristics of whole blood. Explain why it is classified as a connective tissue

-Average volume of blood is 5-6 L for males, and 4-5 L for females Consists of: -Plasma (liquid matrix) -Formed elements (cells and cell fragments) blood is the only fluid tissue in the body. has both cellular and liquid components. is a specialized type of connective tissue in which living blood cells, called the formed elements, are suspended in a nonliving fluid matrix called plasma.

Discuss the composition and functions of plasma

-Blood plasma is the liquid portion of blood *Straw colored ~55% of blood volume ~92% water -Includes transporting nutrients, gases, and vitamins -Helps regulate fluid and electrolyte balance and maintain pH

Describe the structure, function, and production of erythrocytes.

-no nucleus -picks up oxygen in capillary beds of the lungs and releases it to tissue cells across the body -hemoglobin (oxygen) -ATP glycolysis -hormone erythroproietin (kidney)stimulates RBC

Describe the chemical makeup of hemoglobin.

-oxygen -the protein that makes RBC red -binds easily and reversibly with oxygen, and most oxygen is carried in blood is bound to hemoglobin

List functions of blood

1) Transportation-Gases, nutrients, hormones, waste products 2) Regulation-pH, body temperature, osmotic pressure 3) Protection-Clotting, white blood cells, proteins

Describe the ABO and Rh blood groups. Explain the basis of transfusion reactions

A - RBC has A antigen and plasma has B antibody B - RBC has B antigen and plasma has A antibody O - RBC has no antigen, and both A & B antibodies in plasma AB - RBC has both A & B antigens and no antibodies in the blood Rh - Rhesus factor, previously "D" Transfusion reaction - The Ab in your blood causes agglutination which ultimately clogs up capillaries

Give examples of disorders caused by abnormalities of erythrocytes. Explain what goes wrong in each disorder

Anemia Sickle Cell - Mutation affecting the AA sequence of the beta chains in the Hb Thalassemia - Inability to produce adequate amounts of alpha or beta chains of Hb Pernicious anemia - Inability to absorb enough ingested vitamin B12 due to a deficiency of intrinsic factor Nutritional anemia - not enough nutrition Aplastic anemia - failure of bone marrow to produce enough RBCs. Hemolytic anemia - rupture/hemolysis of too many RBCs Polycythemia - abnormal excess of RBC Primary - tumor of bone marrow Secondary - adaptive mechanism, living at high altitude.

List the classes, structural characteristics, and functions of leukocytes.

Granulocytes (granules, all phagocytic) Neutrophils - Polymorphs, Polymorphonuclear leukocytes, effective against bacteria, short-lived, most common Eosinophils - Uncommon, Fights parasitic worms and causes allergies (found with auto-immune and eczema Basophils - release histamine, vasodilation, heparin Agranulocytes - lack visible staining granules T-Lymphocytes - T-cells, direct immune responses, cellular responses B-Lymphocytes - B-cells, Humoral response Natural Killer cells - NK, fight against infected cells

Describe the processes of homeostasis. List factors that limit clot formation and prevent undesirable clotting.

Hemostasis - fast localized response to reduce blood loss through clotting. Three major/overlapping stages. Vascular spasms - vascular phase. Immediate vasoconstriction to reduce blood loss Platelet plug formation- Platelet phase. Normally Prostacyclin lines vessels which prevents coagulation. When the endothelium is broken it causes the collagen fibers to be exposed which induces platelet ADHESION which then ACTIVATES a positive feedback loop which induces AGGREGATION. von Willibrand factor - vWf: secreted by megakayocytes, platelets and endothelial cells, key protein in blood clotting. Coagulation - coagulation phase - blood clotting turns blood from liquid to gel. Using Procoagulants, Ca++, vitamin K and platelets Prothrombin activator formation -> Thrombin -> Fibrin mesh Intrinsic Pathway - damage to inside of vessel, all necessary factors are found within blood, slower. Extrinsic pathway - Triggered by endothelium deprived protein factor called tissue factor, Occurs rapidly.

Describe fluids used to replace blood volume and the circumstances for their use.

Isotonic

Give examples of leukocyte disorders, and explain what goes wrong in each disorder.

Leukopenia - low WBC Leukocytosis - Elevated Leukocyte count Leukemias - clones of a single WBC that remain unspecialized and grow out of control

Describe the structure and function of platelets

Platelets - fragemtns of large "megakaryocytes" each megakaryocyte makes about 1k platelets. Smaller than RBC, but contains Mitochondria, smooth ER and granules, but no nucleus. Granules contain ADP, serotonin and Epinephrine. Three functions - plug, coagulation, tissue repair

Give examples of hemostatic disorders. Indicate the cause of each condition

Thromboembolic disorders-conditions that cause undesirable clot formation -Hemophilia: Caused by a sex-linked trait on the X chromosome, so it occurs primarily in males. Blood clotting disorder where the blood does not clot because of a lack of a protein that is a clotting factor

Describe how leukocytes are produced.

White blood cells (WBCs), also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from multipotent cells in the bone marrow known as hematopoietic stem cells.