1. The Cardiovascular System: The Blood

2. Fluids of the Body Cells of the body are serviced by 2 fluids
blood
composed of plasma and a variety of cells
transports nutrients and wastes
interstitial fluid
bathes the cells of the body
Nutrients and oxygen diffuse from the blood into the interstitial fluid & then into the cells
Wastes move in the reverse direction
Hematology is study of blood and blood disorders

3. Physical Characteristics of Blood
Thicker (more viscous) than water and flows more slowly than water
Temperature of degrees F, pH 7.4
8 % of total body weight
Blood volume
5 to 6 liters in average male
4 to 5 liters in average female
hormonal negative feedback systems maintain constant blood volume and osmotic pressure

4. Formed Elements of Blood
Red blood cells ( erythrocytes )
White blood cells ( leukocytes )
granular leukocytes
neutrophils
eosinophils
basophils
agranular leukocytes
lymphocytes = T cells, B cells, and natural killer cells
monocytes
Platelets (special cell fragments)

5. Red Blood Cells/ Erythrocytes
Transport nutrients & wastes
Contain oxygen-carrying protein hemoglobin that gives blood its red colour (arteries)
Blue (veins)
Biconcave disk
Normal RBC count
new RBCs enter circulation at 2 million/second
Male 5.4 million/drop female 4.8 million/drop

6. RBC Life Cycle Most blood cells types need to be continually replaced
RBCs live only 120 days
wear out from bending to fit through capillaries
no repair possible due to lack of organelles
Worn out cells removed by in spleen & liver
Breakdown products are recycled
New Cell Formation
occurs only in red marrow of flat bones such as the
sternum, ribs, skull & pelvis and ends of long bones

7. Feedback Control of RBC Production
Tissue detects hypoxia (cells not getting enough O2)
Casued by:
1) high altitude since air has less O2
2) anemia
RBC production falls below RBC destruction
3) circulatory problems
Kidney response to hypoxia
speeds up development of new RBCs (proerythroblasts)

8. White Blood Cells/ Leukeocytes
have a nucleus and no hemoglobin
Granular or agranular classification based on presence of cytoplasmic granules made visible by staining
granulocytes are: neutrophils, eosinophils, basophils
agranulocytes are monocyes or lymphocytes

9. WBC Physiology Less numerous than RBCs
1 WBC for every 700 RBC
Only 2% of total WBC population is in circulating blood at any given time
rest is in lymphatic fluid, skin, lungs, lymph nodes & spleen
Detectable changes in numbers of circulating WBCs can indicate:
infection, poisoning, leukemia, chemotherapy, parasites or allergy reaction

10. Differential WBC Count
Destroy foreign elements
Critical to the immune system
Normal WBC counts
neutrophils 60-70% (up if bacterial infection)
lymphocyte 20-25% (up if viral infection)
monocytes % (up if fungal/viral infection)
eosinophil % (up if parasite or allergy reaction)
basophil <1% (up if allergy reaction)

11. Platelet (Thrombocytes)
Platelets form in bone marrow
Their sticky surface lets them form clots to stop bleeding.
Short life span (5 to 9 days in bloodstream)
formed in bone marrow
few days in circulating blood
aged ones removed in liver and spleen

12. Blood Loss Prevention
Stoppage of bleeding in a quick & localized fashion when blood vessels are damaged
Prevents hemorrhage (loss of a large amount of blood)
Methods utilized
vascular spasm
platelet plug formation
blood clotting
(coagulation = thickening of blood)

13. Complete Blood Count Screens for anemia and infection
% of Blood Volume
-Plasma 55% of volume
- 90% water, other dissolved substances in the plasma include gases, nutrients (protein) & ions)
- Hematocrit 45%
- Total RBC (99%), 1% (WBC & platelets)

14. Blood Groups and Blood Types
RBC surfaces are marked by genetically determined glycoproteins & glycolipids
agglutinogens or isoantigens
distinguishes at least 24 different blood groups

15. ABO Blood Groups
Based on 2 glycolipid isoantigens called A and B found on the surface of RBCs
display only antigen A -- blood type A
display only antigen B -- blood type B
display both antigens A & B -- blood type AB
display neither antigen -- blood type O
Plasma contains isoantibodies to the A or B antigens not found in your blood
anti-A antibody reacts with antigen A
anti-B antibody reacts with antigen B

16. +ve/ -ve RH blood groups
Antigen was discovered “Rhesus” monkey blood
People with Rh agglutinogens are Rh+ve.
- Normal plasma contains no anti-Rh antibodies
Antibodies develop only in Rh-ve blood type & only with exposure to the Rh+ve antigen
transfusion of positive blood
during a pregnancy with a positive blood type fetus
Transfusion reaction upon 2nd exposure to the antigen results in breaking down of the RBCs in the donated blood

17. Hemolytic Disease of Newborn
Rh negative mom and Rh+ fetus will have mixing of blood at birth
Mom's body creates Rh antibodies unless she receives a RhoGam shot soon after first delivery, miscarriage or abortion
RhoGam binds to loose fetal blood and removes it from body before she reacts
In 2nd child, hemolytic disease of the newborn may develop causing hemolysis (break down) of the fetal RBCs

18. Anemia = Not Enough RBCs
Symptoms
oxygen-carrying capacity of blood is reduced
fatigue, cold intolerance & paleness
lack of O2 for ATP & heat production
Types of anemia
iron-deficiency =lack of absorption or loss of iron
hemorrhagic = loss of RBCs due to bleeding (ulcer)
hemolytic = defects in cell membranes cause rupture
thalassemia = hereditary deficiency of hemoglobin
aplastic = destruction of bone marrow (radiation/toxins)

19. Hemophilia Inherited deficiency of clotting factors
bleeding spontaneously or after minor trauma
subcutaneous & intramuscular hemorrhaging
nosebleeds, blood in urine, articular bleeding & pain
Treatment is transfusions of fresh plasma or concentrates of the missing clotting factor

20. Leukemia Acute leukemia Chronic leukemia
uncontrolled production of immature leukocytes
crowding out of normal red bone marrow cells by production of immature WBC
prevents production of RBC & platelets
Chronic leukemia
accumulation of mature WBC in bloodstream because they do not die
classified by type of WBC that is predominant