Unit 7 Part 1 Blood and Heart Notes

Unit 7 Part 1: Chapter 10: Blood

  • Plasma – Liquid portion (55% of volume)  {Picture below shows the plasma with red blood cells, white blood cells, platelets and other formed elements floating in the plasma as well as a clotted fibrin mesh/repair of the blood vessel in the lower right hand corner}


  • Formed Elements – Cells and fragments suspended in plasma (45% of volume)


  • Components of blood are continually destroyed and produced (millions each second).  

I.                   Three types of Formed Elements 

1) Erythrocytes (Red Blood Cells) 

2) Leukocytes (White Blood Cells)  


A) Granular Leukocytes

1- Neutrophils

2 – Eosinophils

3 – Basophils

B) Non-granular Leukocytes           

1- Lymphocytes

2- Monocytes

3)  Thrombocytes (Platelets) 

  • 1 drop of blood in the average person contains; 5 million RBC’s, 7,500 WBC’s, and 300,000 Platelets


II.                Functions of Formed Elements 

1.      Erythrocytes – O2 and CO2 Transport

2.      Leukocytes

  • ·        Granular ---Made by Bone Marrow

a.  Neutrophil – Immune defense (Phagocytosis) (most numerous)

b.  Eosinophil – Defense against parasites

c.  Basophil – Inflammatory response

  • ·        Non-Granular --- Made By Lymph Glands and Lymph Tissues

a.  B-Lymphocyte – Antibody production

b.  T-Lymphocyte – Cellular Immune Response

c.  Monocyte – Immune Defense (Phagocytosis) 

3.       Platelet (Thrombocytes) – Blood Clotting

  • ·        Platelets are cell fragments that travel in the blood joined together in a Megakaryocyte 

III.             Formation of Blood Cells 

1.      Blood is a form of connective tissue (Hemopoetic tissue) 

2.      2 Types of connective tissue 

·        Myeloid Tissue (Red Bone Marrow)

1.      Found in ribs, sternum, and hipbones

2.      Forms all types of blood cells except non - granular leukocytes (lymphocytes and monocytes). 

·        Lymphatic Tissue

1.      Found in lymph nodes, thymus, and spleen

2.      Form lymphocytes and monocytes.  

IV.              Erythrocytes (Red Blood Cells) 

·        Shape and number provides an enormous area for exchange of O2 and CO2.

·        Cells resemble concave disks.

·        Hemoglobin (red pigment) binds with O2 to form oxyhemoglobin.

·        Each hemoglobin has four iron sites “Heme Groups” for oxygen to bind to.

·        Iron deficiency means less O2 can bind with hemoglobin 

V.                 Hematocrit 

·        Hematocrit – Test determines volume of RBC’s by spinning blood in centrifuge to separate RBC’s from WBC’s and platelets

o       3 Layers

§         Plasma (least dense)

§         Buffy Layer (WBC’s and Thrombocytes)

§         Red Blood Cells 

VI.              Erythrocytes Problems/Anemia (Red Blood Cells) 

·        Anemia – Disease caused by an inability to carry sufficient O2 to body cells. (Inadequate number, shape, or deficiency in hemoglobin)

·        Pernicious anemia – Deficiency of Vitamin B12.

·        Polycythemia – Bone marrow produces an excess of RBC’s which makes blood too thick to flow.

·        Iron Deficiency Anemia – Body cannot make enough hemoglobin.

·        Sickle Cell Anemia – Genetic condition in which the blood cells are shaped like a sickle. 

o       Found in mostly people with African descent.

·        Anemia results in less hemoglobin, less O2 in blood, slower breakdown of nutrients, less energy, and fatigue.  

VII.           Leukocytes (White Blood Cells) 

·        Defend body from invading microorganisms.

o       Neutrophils and Monocytes – Phagocytosis

o       B-Lymphocytes – Produce antibodies.

o       T-Lymphocytes – Attack microbes.

o       Eosinophils – Protect against irritants which cause allergies.

o       Basophils – Aid against allergies and contain Heparin (Prevents blood from clotting as it flows).  More made to fight infections. 

VIII.        White Blood Cell Problems 

·        Leukopenia – Low WBC count (Less than 5,000)= AIDS

·        Leukocytosis – High WBC count (More than 10,000)= infection

·        Leukemia – High WBC count (Blood Cancer) 

IX.              Platelets and Blood Clotting 

·        Series of rapid reactions 

1) Injury to blood vessel 

2) Blood platelets break as they encounter jagged surfaces. 

3) Platelets release platelet factor (sticky substance attracting more substances). 

4) Platelet factor combines with Prothrombin (protein) and calcium to form Thrombin. 

5) Thrombin reacts with fibrinogen (protein) to produce fibrin (tangle of fine threads). 

o       A clot which forms in an unbroken blood vessel is called a thrombus. (Does not move through body)

o       If clot dislodges and circulates it is called an embolus.  

X.                 Blood Plasma 

·        Liquid portion of blood that carries water and substances needed to survive (food, salts, and small amounts of oxygen)

·        Also transports cellular wastes to excretory organs and transports hormones and antibodies.

·        Serum – Plasma minus its clotting factor. 

XI.              General Facts About Blood 

·        More blood in a larger person.

·        More blood in men.

·        4 – 6 L of blood in average person (7 –9% of body weight).

·        Slightly Alkaline – Ph of 7.35 to 7.45 

XII.           Blood Types 

·        Identified by antigen in  RBC’s.

o       Antigen – Stimulates body to produce antibodies.

o       Antibody – Substance made in response to antigen. 

·        4 Types

o       Type A (40%)           

o       Type B  (11%)          

o       Type AB (4%)                       

o       Type O  (45%)             

·        Type A

o       A antigens

o       Type B will agglutinate (clot)

·        Type B

o       B antigens

o       Type A will agglutinate

·        Type AB

o       A and B antigens

o       No Antibodies:  Universal Recipient

·        Type 0

o       No antigens: Universal Donor

o       A and B Antibodies  

XIII.        Rh System (+ or -) 

·        Rhesus Factor

o       Antigen that is located on the surface of Red Blood Cells if present

o       Rh positive – Body contains Rh antigen (most)

o       Rh negative – Does not contain Rh factor

XIV.        Rh Factor and Pregnancy 

·        Dangerous in babies born to Rh- mother and Rh+ father.

§         If baby inherits Rh+, mother may produce Anti Rh antibodies upon mixing of mothers and baby’s blood.

§         If mother carries another Rh+ baby, Erythroblastosis fetalis (agglutination of baby’s blood).

§         Can occur in first born if hemorrhages occur

§         Blood does not carry enough oxygen

§         Rh- mothers are usually treated with Rhogam (immunosuppressant) after birth of first baby to prevent formation of Anti Rh antibodies.