1. Red Blood Cells
Formation and structure

2. Regulation of RBC Production
Decrease in oxygen in blood
Hemorrhage
Excessive RBC destruction
Decreased oxygen availability
Hypoxia
Higher altitudes  decreased oxygen availability

4. Platelets Also called thrombocytes. Important in blood clotting:
Smallest of formed elements.
Important in blood clotting:
Constitute most of the mass of the clot.
Release serotonin to reduce blood flow to area and ADP to cause pseudopodia to grow.
Secrete growth factors
Maintain the integrity of blood vessel wall.

6. RED BLOOD CELL ABNORMALITIES
Anemia
Polycythemia
Sickle Cell Anemia

7. Anemia General definition – reduced O2 carrying capacity Causes:
Low number of erythrocytes
Hemorrhage – blood loss
Hemolytic – ruptured RBC’s
Aplastic – inability of bone marrow to synthesize RBC
Decreased hemoglobin
Iron-deficiency
Athletes anemia – expanded blood volume
Pernicious anemia – B12 deficiency or lack factor for B12 absorption

8. Polycythemia Over production of RBCs Hematocrit = 80% (normal = 45%)
Cause: bone marrow cancer
Symptoms: headache, dizziness, blood clots
Secondary causes
Adaptation to high altitude
Blood doping
Supplemental Erythropoeitin

9. Sickle Cell Anemia Shape of erythrocyte is altered
1 amino acid (out of 267) is different in hemoglobin
Blood cells have a crescent shape
Decreased organ blood flow

10. White blood cells (Leukocytes)
How do they differ from erythrocytes?
Contain nuclei and other cell organelles
Almost invisible under a microscope
Lifespan: 12 hours300 days
Types of Leukocytes:
Neutrophils, lymphocytes, monocytes, eosinophils, basophils
Bacterial or viral infection: increased WBC production

11. WBC disorders Leukopenia – low WBC count (nutrition/ radiation)
Leukemia – cancer of WBC
Large number of immature, non-functioning WBCs
Anemia
Hemorrhage
Massive infections

12. Blood types
RBC plasma membranes have specific antigens which are unique
A,B,AB (universal recipient), O (universal donor)
Rh negative or Rh positive (85% of population)

13. Red Blood Cell Antigens
ABO system:
Major group of antigens of RBCs.
Type A:
Only A antigens present.
Type B:
Only B antigens present.
Type AB:
Both A and B antigens present.
Type O:
Neither A or B antigens present.

14. RBC Antigens Type B: Type AB: Type O:
May have inherited B gene from each parent.
May have inherited B gene from 1 parent and O gene from the other parent.
Type AB:
Inherited the A gene from one parent and the B gene from the other parent.
Type O:
Inherited O gene from each parent.

15. Transfusion Reactions
If blood types do not match, the recipient’s antibodies attach to donor’s RBCs and agglutinate.
Type O:
Universal donor.
Recipient’s antibodies cannot agglutinate the donor’s RBCs.
Type AB universal recipient:
Lack the anti-A and anti-B antibodies.
Cannot agglutinate donor’s RBCs.

16. Rh Factor Another group of antigens found on RBCs. Rh positive:
Have these antigens.
Rh negative:
Do not have these antigens.
Significant when Rh negative mother give birth to Rh positive baby.
At birth, mother may become exposed to Rh positive blood of fetus.
Mother at subsequent pregnancies may produce antibodies against the Rh factor.

18. Fig. 4.12

19. Reading thus far:
Pages : Circulatory system, WBC, RBC, hematopoiesis, hemostasis, blood types
Pages : Heart anatomy, structure, cardiac circulation
Page 354: Cardiac muscle fibers