EPOB 3430 2/25/03 If you haven`t yet picked up your exam, you can

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IPHY 3430 10-04-11
Circulatory System
Purposes:
Delivery of O2, energy containing
substrates, vitamins and other nutrients
to cells;
Removal of CO2, secretory products, and
waste products from cells.
Topics
a. blood constituents
b. transport of gases
c. heart function
d. blood pressure
e. blood volume and lymphatic system
Additional components of the
circulatory system:
Medulla vasomotor center
SNS, PNS
And, blood...
Components of Blood:
Cells: red blood cells, white blood cells,
and platelets
Plasma: water
proteins
a. Albumin
b. globulins (,,)
c. Fibrinogen
ions
glucose, amino acids
wastes (creatinine, urea, ammonia)
Transport of Oxygen
3% transported dissolved in plasma
97% transported in red blood cell in
association with hemoglobin
Red blood cells
Men: 5 million/ml blood
Women: 4.5 million/ml blood
25-30 trillion rbc’s in total blood volume
120 day life span
no nucleus, mitochondria nor ribosomes
4 heme groups (Fe plus pyrroles) + 4 globin
molecules
Hemoglobin binding
on heme groups
1. O2
2. CO
on globin chains
3. CO2
4. H+
5. Nitric oxide (NO)
6. 2,3 biphosphoglycerate
Regulation of red blood cell production
 RBCs (O2 delivery) ---> Kidney (both
sensor and integrator)--->  secretion of
erythropoietin -->  stimulation of bone
marrow to produce RBCs --> RBCs (O2
delivery)
 RBCs (O2 delivery) ---> Kidney (both
sensor and integrator)--->  secretion of
erythropoietin --> stimulation of bone marrow
to produce RBCs --> RBCs (O2 delivery)
Pathological variation in RBCs
Anemias (30% and below)
1. Iron deficiency
2. Lack of folic acid in diet
3. Pernicious
4. Hemorrhagic
5. Aplastic
6. Hemolytic
7. Renal
Regulation of red blood cell production
 RBCs (blood PO2) ---> Kidney (both
sensor and integrator)--->  secretion of
erythropoietin -->  stimulation of bone
marrow to produce RBCs --> RBCs (PO2)
 RBCs (blood PO2) ---> Kidney (both
sensor and integrator)--->  secretion of
erythropoietin --> stimulation of bone marrow
to produce RBCs --> RBCs (PO2)
Pathological variation in RBCs
Polycythemia (70% and above)
1. Polycythemia vera
2. Chronic high altitude mountain sickness
Relation between hematocrit and oxygen
transport
Normal hematocrit
Blood doping
O2
transport
Hematocrit