Blood Flashcards
Percent of RBC in blood volume but sometimes it is all cells since
the rest is negligible to RBC
* 47% ± 5% for males
* 42% ± 5% for females
Hematocrit
level of oxygenated protein in RBC
* pH 7.35–7.45 = basic or acidic
Hemoglobin
Distribution of
* O2 and nutrients to body cells
* Metabolic wastes to the lungs and kidneys for elimination
* Hormones from endocrine organs to target organs
Functions of Blood
Regulation of
Body temperature by absorbing and distributing heat =
mostly water in plasma
Normal pH using buffers
Adequate fluid volume in the circulatory system
Functions of Blood
Protection against
Blood loss
Plasma proteins and platelets initiate clot formation
Infection
Antibodies
Complement proteins
WBCs defend against foreign invaders
Functions of Blood
- 90% water
- Proteins are mostly produced by the liver
Antibodies made by WBC
Blood Plasma
- RBCs are dedicated to
respiratory gas transport - Hemoglobin binds
reversibly with oxygen
Erythrocyte Function
- Hemoglobin structure
- Protein globin: two alpha and two beta chains
- Heme pigment bonded to each globin chain
Erythrocyte Function
- Iron atom in each heme can bind to one O2 molecule
- Each Hb molecule can transport four O2
Erythrocyte Function
blood cell formation
* Occurs in red bone marrow of axial skeleton, girdles and
proximal epiphyses of humerus and femur
Hematopoiesis (hemopoiesis)
Too few RBCs leads to tissue hypoxia (low
oxygen)
Too many RBCs increases blood viscosity (blood
sticky, danger of thrombus)
Hematopoiesis (hemopoiesis)
- Causes of hypoxia (low oxygen)
- Hemorrhage of vessel (vessel tears)
- Increased RBC destruction (lysis of RBCs by infections) reduces RBC numbers
Hormonal Control of Erythropoiesis
- Insufficient hemoglobin (e.g., iron deficiency)
- Reduced availability of O2 (e.g., high altitudes, low oxygen environments)
