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Blood cells Notes

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					   Blood
 Function of Blood
Composition of Blood
   Blood Types
Function of Blood
 Transport    of:
           Oxygen, Carbon Dioxide
             Nutrients, Wastes
                Hormones

 Immunity
      – Protects the body against invaders

 Distribution    of heat around
 the body
   Composition Of
      Blood
 55   % Plasma

 45%    Cells and Cell
 Parts
                  Plasma
   clear golden fluid composed of:
     – Water
     – dissoved substances
     – proteins
   Has several functions:
     – Transports small molecules and ions
     – contains proteins involved in blood clotting
     – contains antibodies that are involved in disease
       fighting
   Blood Cells and
      Cell Parts
There are 3 Cellular components to blood
 Red Blood Cells
 White Blood Cells
 Blood Platelets
Red Blood Cells
 Also called Erythrocytes
 Approx. 6 billion RBCs per mL of blood
 Main function is to carry Oxygen
 Structure:
    – Mature cells do not contain a nucleus
    – Flattened doughnut shape
    – Contain oxygen-carrying hemoglobin
      molecules
White Blood Cells
    also called Leucocytes
    Function: protect the body from infection
     – Numbers increase during an infection
 There are Two main types of W.B.C. s
  macrophages
     – move out of capillaries and digest foreign
       materials by phagocytosis
    Lymphocytes
     – manufacture antibobies that fight infection
              Platelets
 Cell fragments
 250 million per cubic centimetre
 Function: Trigger the Blood Clotting
  Process
               Review of Blood
                Components
                                      Blood


        Plasma               Blood Cells and Blood Parts


  White Blood Cells(W.B.C)            Platelets            Red Blood Cells (R.B.C)
        -Leucocytes                                            -Erththrocytes


Macrophages      Lymphocytes
             Blood Clotting
   Platelets broken open by damaged blood
    vessels
   Platelets release chemicals that convert
    prothrombin into thrombin (requires Calcium
    ions)
   Thrombin reacts with fibrinogen molecules to
    form fibrin (an insoluble fibrous protein)
   Many strands of fibrin form a mesh or clot that
    stops the bleeding
Blood Clotting
          Important Terms
Antigen                   Antibody
 Molecules that           Proteins found in
  cause the synthesis       blood that attack
  of antibodies when        and neutralize
  injected into another     substances that are
  organism                  foreign to the body
         Major Blood Groups
   Discovered by Karl Landsteiner
   Different blood groups are due to differing
    antigens present on red cell membranes
   4 Major Blood Types
    –   A
    –   B
    –   AB
    –   O
    BLOOD TRANSFUSIONS
   Not all blood types can be mixed together
   If the wrong Blood types are mixed a process
    called Agglutination will occur

Agglutination - the clumping of blood

   Examine the next chart to see compatible
    blood groups
    Blood Compatibilities
Blood Type   Antigen     Antibody
    A            A         Anti B
     B            B        Anti A
    AB         A and B      None
    O           None     Anti A and
                          Anti B
    Blood Transfusions
 Since Type O Blood contains no antigens, it
 can be safely transfused into any blood type
 Type O = “the universal donor”

Since Type AB has no antibodies, any other blood
type can be safely transfused into it
Type AB = the “universal receipient”

All other combinations will produce agglutination
            Rh Factors
 Other antigens that may be present on
  R. B C. s
 Most people have these antigens they
  are said to be Rh Positive
 Those without the antigen are said to be
  Rh Negative
    Rh Factors and Pregancy
 Problems may occur if Rh negative
  mother gives birth to Rh positive baby
 Mother may develop anti-Rh antibodies
 Future pregnancies may result in these
  antibodies causing agglutination of
  baby’s blood
 However injections have been
  developed that correct this problem
            Blood Problems
   Anemia - occurs when there is a shortage of
    hemoglobin ib blood
   Leukemia - Cancer of the white blood cells
   A.I.D.S - the H.I.V. virus attacks and destroys
    an important type of WBC
   Sickle Cell Disease - abnormal hemoglobin
    causes RBC s to have irregular shape

				
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