1. NOTES: UNIT 6- Blood

2. Blood is a type of connective tissue whose cells are suspended in a liquid intercellular material. It transports substances between body cells and the external environment, and helps maintain a stable internal environment.

3. 3 Functions of Blood: DISTRIBUTION: REGULATION: PROTECTION:
Deliver oxygen & nutrients to all body cells
transport waste products from cells to elimination sites
Transporting hormones to target organs
REGULATION:
Maintain appropriate body temperature
Maintain normal pH
Maintain adequate fluid volume
PROTECTION:
Prevent blood loss
Prevent infection

4. BLOOD AND BLOOD CELLS
Blood can be separated into formed elements and liquid portions.
• Formed elements (45%):
-Mostly red blood cells (RBCs)
-Include white blood cells (WBCs) and platelets
• Liquid portions = PLASMA (55%)
-Water, gases, nutrients, hormones,
electrolytes, and cellular wastes

5. Blood Volume: FYI Whole blood counts for about 8% of total body weight
The average adult female body contains 4-5 L of blood, and the average adult male contains 5-6 L
Total surface area of all the RBC’s in an adult is larger than a football field!

6. Red Blood Cells (RBCs) • Biconcave disc shaped to
increase surface area
• Contain HEMOGLOBIN,
which combines with oxygen
• Produced in the red bone marrow (process  Hematopoiesis)
• RBC production is influenced by vitamin B-12 and folic acid
• Hemoglobin synthesis requires IRON

7. Red Blood Cells… Men on average have more RBCs (testosterone)
Are unable to grow or to divide (no nucleus)
Have a useful lifespan of 100 to 120 days
Old cells are filtered out by the liver and spleen

9. White Blood Cells (WBCs)
• Function in defense against disease
• Include several different types
• Normal WBC count is 4,000 – 11,000 cells per mm3 of blood
 This number may vary in response to infection, emotional disturbances, loss of body fluids, leukemia

10. White Blood Cells…
Are the only formed elements that are complete cells
Nucleus & usual organelles
Can leave the bloodstream and slip into tissues and lymphoid tissue

11. Platelets • Fragments of larger cells • Develop in red bone marrow
• Help close breaks in blood vessels / clot the blood

13. PLASMA
Plasma transports gases and nutrients, helps regulate fluid and electrolyte balance, and helps maintain a stable pH.

14. PLASMA  Gases in plasma: -Oxygen -Carbon dioxide -Nitrogen
Plasma nutrients:
-Simple sugars
-Amino acids
-Lipids
-Electrolytes
Other materials
Hormones
Waste products

15. HEMOSTASIS (= stoppage of bleeding)
Following an injury, hemostasis may occur due to:
1) Blood vessel spasm
2) Platelet plug formation
3) Blood coagulation

16. 1) Blood vessel spasm:
-Smooth muscles in blood vessel walls contract following an injury
-Platelets release a chemical, which stimulates vasoconstriction

17. 2) Platelet plug formation:
-Platelets adhere to the rough surfaces and exposed collagen of injured area
-Platelets adhere to each other and form platelet plugs

19. 3) Blood coagulation -Most effective means of stopping bleeding
-Plasma protein FIBRINOGEN is converted into FIBRIN
-FIBRIN threads create a
meshwork that traps
blood cells and platelets
 BLOOD CLOT

20. Conditions that Oppose Clotting
A few factors will oppose blood clotting
Healthy lining of blood vessels
Antithrombins- Heparin (medicine)
Conditions that Hasten Clotting
A few factors will speed up clotting
Rough spot in the blood vessel lining
Atherosclerosis (disease of blood vessels)

21. BLOOD CLOTS… • THROMBUS = an abnormal clot in a blood vessel
• EMBOLUS =
a clot or clot fragment
that breaks away and
moves

22. BLOOD GROUPS AND TRANSFUSIONS
Blood is typed based on cell surface antigens (protein markers)
• RBC membranes may contain certain antigens
(A, B, Rh)
• Blood plasma may contain antibodies against some of these antigens
 RESULT: following a transfusion of the wrong blood type, the RBCs may clump in a process called AGGLUTINATION

23. Antibodies with matching shape to the Antigen on the RBC

24. ABO Blood Group:
• blood is grouped according to the presence or absence of antigens A and B.
Blood Type (phenotype)
Possible genotypes
Antigen(s)
Antibodies (immune system makes against the antigen)
Type A
AA; AO A
Anti-B
Type B
BB; BO B
Anti-A
Type AB AB
A and B
none
Type O OO
Anti-A and Anti-B

26. ABO Blood Group:
• Mixing RBCs that contain an antigen with plasma that contains the corresponding antibody results in a negative reaction (AGGLUTINATION)
*The anti-A and anti-B
antibodies are too large
to cross the placenta,
so mother and child can
safely have different ABO blood groups

27. When blood is donated, ONLY the RBC is transferred to the recipient; NOT the donor’s antibodies!

28. How a lab determines your blood type:

29. Rh Blood Group: • Rh-positive blood: RBC’s have Rh antigens
• Rh-negative blood: RBC’s don’t have Rh antigens, but may possess anti-Rh antibodies (if exposed to Rh+ blood)
 RESULT: mixing Rh-positive RBCs with plasma that has the anti-Rh antibodies can result in agglutination

30. Rh Blood Group:
*The anti-Rh antibodies are small enough to cross the placenta…
So, the anti-Rh antibodies in a mother’s blood could react with the RBC’s of an Rh-positive fetus

31. The “Rh Issue”… Mom = Rh- Baby #1 = Rh+

32. Blood Disorders
Most blood disorders occur from disorders of the formed elements
May occur during formation in the blood marrow
If blood marrow is suspected, some can be aspirated from the hip and tested
A bone marrow transplant may follow if there is diseased tissue

33. RBC Disorders
Anemia
Any disorder caused by the inability of the blood to carry sufficient oxygen supplies
Aplastic anemia- may occur from a decreased # of RBC’s due to cancer, radiation damage, infections
Pernicious anemia- a decreased # of RBC’s because of a vitamin B12 deficiency
Iron deficiency anemia- decreased amount of hemoglobin due to a lack of
iron (usually in the diet)
Hemolytic anemia- any type
of anemia due to abnormal types
of hemoglobin
Includes sickle cell anemia

34. Normal bone marrow. aplastic anemia marrow
Normal bone marrow aplastic anemia marrow (fatty tissue instead of cells)

35. WBC Disorders Other Blood Disorders
AIDS- virus (HIV) which kills certain immune system cells
Leukemia- Cancer of the WBC’s
May be caused by defective bone marrow
Other Blood Disorders
Hemophilia- genetic disorder in which individuals lack factors (proteins) necessary for clotting to occur

36. More Blood Info
Individuals who live in high elevations may have elevated RBC #’s which is called physiological polycythemia
Body’s way to adapt to lower levels of oxygen in the atmosphere
Why athlete's train at higher altitudes and the idea behind blood doping (more RBC’s, more oxygen in body)
Doping can be dangerous because this decreases the level of plasma in the blood