I.
Blood Composition: Red Blood Cells, White Blood Cells, Platelets
and Plasma
A.
Red Blood Cells or Erythrocytes- 45% of blood
1.
Biconcave shape related to cells function of transporting gases (O2 to
cells and CO2 away from cells)
2.
Hemoglobin- Oxygen carrying compound
a. Hemoglobin + O2 = oxyhemoglobin (red)
b. Hemoglobin - O2= deoxyhemoglobin (dark)
3.
Red Blood Cell Count (RBC)
a. Male=4.6-6.2 million/mm^3
b. Female=4.2-5.4 million/mm^3
4.
Liver and spleen destroy damaged red cells by macrophages
a. RBC usually live for 120 days
5.
Biliverdin and Bilirubin are result of broken down red blood cells are
secreted as bile
6.
Production – at birth red cells are produced in egg yolk, liver and
spleen; in adults the production is in red bone marrow
a. Erythropoietin (EPO)- hormone released due to oxygen deficiency which
stimulates production of red bloods cells
b. Hemocytoblast- origin of red blood cells
c. B12 and Folic Acid- essential for red blood cells development in infants. Iron
can be recycled.
B.
White Blood Cells- Leukocytes fight various disease and control
infection
1.
Granulocytes- Neutrophils, Eosinophils and Basophils – 12 hour life
spans
a. Neutrophils- granular with 2-5 part nucleus (54-62% of WBC )
b. Eosinophils- granular with 2 lobed nucleus 1-3% of WBC
c. Basophils- similar to Eosinophils with fewer granules. Less than 1% of WBC
2.
Agranulocytes- Monocytes and Lymphocytes
a. Monocytes-largest blood cells; nuclei is kidney shaped “lobed” 3-9% of
Leukocytes
b. Lymphocytes- large round nucleus 25-33% of WBC
C.
3.
White Blood Cell counts 5-10 thousand
a. More than 10 thousand is diagnosed as leukocytosis
b. Less than 5 thousand is leukopenia
4.
Function of White Blood Cellsa. Leukocytes leave the bloodstream- diapedesis
b. Neutrophils and Monocytes contain lysosomes to break down protein coats
and lipids (phagocytosis)
c. Eosinophils- fight allergic reaction and are slightly phagocytosis
d. Basophils- contain anti-coagulant Heparin and Histamine
e. Lymphocytes- form antibodies to boost immunity
Platelets- Thrombocytes
1.
Produced by Megakaryocytes in red marrow by releasing cytoplasmic
fragments
D.
2.
Life span 10 days
3.
Platelet count 130-360,000/mm^3
4.
Form blood clots
Plasma – 55% of blood
1.
Composed of 92% H2O, amino acids, proteins, carbohydrates, lipids,
vitamins, hormones, electrolytes and cellular waste
2.
Plasma proteins
a. Albumins- 60% of plasma proteins; help maintain osmotic pressure
b. Globulins- 36% of plasma protein- alpha, beta and gamma globulins
c. Fibrinogen- 4% essential in blood clotting