I   Introduction

            A.  Composition

                        1.  formed elements

                                    a.  erythrocytes (RBC)

                                    b.  leukocytes (WBC)

                                    c.  platelets


                        2.  plasma

                                    a.  fluid:  water, ions, hormones

                                    b.  proteins (most made in liver)

                                                1.  albumins

                                                2.  globulins

                                                            a.  alpha and beta

                                                            b.  gamma

                                                3.  fibrinogen

            B.  Function to maintain homeostasis

                        1.  transport

                        2.  buffers

                        3.  immunity


II  Erythrocytes                                                                                   

          A.  Function

                        1.  gas transport

                        2.  hemoglobin structure

            B.  RBC

                        1.  formation from hematocytoblast in red marrow

                        2.  loss of organelles

                        3.  biconcave shape

                        4.  structure and function correlation

            C.  Life cycle

                        1.  erythropoiesis

                                    a.  negative - feedback regulation

                                                1.  erythropoietin

                        2.  120 days ---> destruction

                        3.  recycling                                                           

                                    a.  bilirubin; jaundice

            D. Surface markers (antigens)                                                        (blood typing game)

                        1.  ABO group

                                    a.  type A:  A antigens, antibodies to B in plasma

                                    b.  type B:  B antigens, antibodies to A in plasma

                                    c.  type AB:  both A and B antigens, no antibodies in plasma

                                    d.  type O:  no antigens, antibodies to both A and B in plasma

                        2.  agglutination reaction:  antibody “clumps” antigens

                        3.  Rh system                            

                                    a.  Rh+:  Rh antigen

                                    b.  Rh- :  no Rh- antigen (no antibodies to Rh+ unless exposed to Rh+ antigen)

                                    c.  hemolytic disease of newborn

                                                1.  Rh-  mom and Rh+  fetus

                                                2.  Rhogam


III   Platelets

            A.  Formation

                        1.  hematocytoblast --> megakaryocyte --> platelets (cell fragments)

            B.  Function

                        1.  help in hemostasis

                                    a.  plug formation

                                    b.  clot formation

            C.  Hemostasis stages                                               (hemostasis animation)

                        1.  vascular spasm

                        2.  platelet plug formation

                                    a.  collagen exposure                               

                                    b.  platelets adhesion

                                    c.  ADP release; thromboxane release

                                                1.  aspirin inhibits at this stage

                                    d.  platelet accumulation = plug

                        3.  clot formation

                                    a.  clot definition


                                    b.  cascade reactions

                                                1.  inactive precursors

                                                2.  final stages

                                                            a.  prothrombin ------> thrombin

                                                                        1.  heparin effects

                                                            b.  fibrinogen -------> fibrin (clot)


IV Leukocytes

                 A.  General function

                        1.  mobile defense

                                    a.  diapedesis

            B.  Categories and functions

                        1.  polymorphonuclear granulocytes

                                    a.  eosinophils

                                                1.  parasites and allergies

                                    b.  basophils

                                                1.  histamine

                                    c.  neutrophils

                                                1.  phagocytes

                        2.  mononuclear agranulocytes

                                    a.  monocytes

                                                1.  macrophages

                                    b.  lymphocytes

                        3.  diagnostic value

            C.  Non- Specific Defense

                        1.  all of above except lymphocytes

            D.  Specific Defense

                        1.  lymphocytes

                                    a.  maturation

                                    b.  types

                                                1.  T-cells


                                 SEM: cytotoxic lymphocyte (top) in the act of recognizing a tumor cell (bottom right).

                                                    Denis M. Callewaert,  PhD. Biochemistry, Oakland University


                                                            a.  antigen recognition

                                                            b.  types and role

                                                                        1.  cytotoxic

                                                                        2.  helper

                                                                        3.  suppressor

                                                            c.  cell-mediated immunity

                                                2.  B-cells

                                                            a.  antigen recognition

                                                            b.  antibody production

                                                                        1.  plasma cells

                                                            c.  humoral immunity



Questions you should be able to answer at the end of this unit:



- list the components of the plasma and what they do

- describe the structure of a hemoglobin molecule

- explain where gases attach to hemoglobin and the conditions needed for the binding and release of each gas

- describe the structure of an erythrocyte and how its structure fits its function

- explain the triggers and process of erythropoiesis

- describe the fate of worn out RBCs and the hemoglobin inside of them

- draw a RBC from each of the ABO blood groups and the antibody that accompanies it

- determine the possible donors and recipients of each blood type and explain the reasoning

- name the components of an agglutination reaction

- discuss the problem that might occur in an Rh- pregnant woman

- list the sequence of events needed for hemostasis with small lesions versus larger lesions

- explain how a platelet plug is formed and how the size of the plug is controlled

- explain the advantage of cascade reactions and inactive precursors in blood clotting

- explain how aspirin, heparin, and Coumadin (warfarin) interfere with clotting

- explain the role of tPA and how it is used in hospitals

- compare the structure and function of a "clump", "plug", and  "clot"

- compare similarities and differences of leucocytes and erythrocytes

- list the WBCs which provide non-specific immunity and explain what each does

- explain the difference between specific and non-specific immunity

- describe the role of B lymphocytes and  the role of T lymphocytes in specific immunity

- compare humoral defense and cell-mediated defense and explain why both are needed

- explain the link between HIV and "helper" T-cells




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